You're over analyzing it, I feel.
It really has little to do with ethics, gender roles, or the current mentality of how people view gender or ethnicity.

Kamen Rider is a franchise aimed at boys, made to sell toys, and that will forever be it's purpose. They've already noted female figures tend to have lower sales, so their hesitance is to put a woman in the lead role might have a noticeable decline in sales altogether. They're not trying to push women down because of antiquated ideals. They just want the highest toy sales possible.

Note that this isn't to say that there aren't any bad apples in Bandai and Toei's higher ups, but honestly, the whole issue of having a woman as a main rider is less gender politics, and more just straight money and sales determining the future of a franchise.

Agreed. But the problem that lies there is the fact that the girls sell less because the target demographic isn't used to seeing them. When something different occurs it's very off-putting to lots of people. It's not that certain groups of people prefer certain objects, media or lifestyles; it's that the general public has been conditioned to believe such things. And that has an effect on society, like all media does.

Because of that "female" things end up selling less for franchises like this, which gives companies stats that show more "boy" things sell than "girl" things, so they make more "male" merchandise. And then the general public see it, think the shows, games & whatever else they make has more to do with males than females, so more male things sell & buy the items & the cycle continues.

Change will not occur until someone in power is willing to take a risk & break the cycle, but they can't because they created it themselves & it's the cycle that gives them their good business & changing it would mean a drop in sales, which is something no business wants.

And it's not like lower sales for "male" merchandise means they're gonna shift over to "female" merchandise for Kamen Rider. They created multiple franchises for, in their mind, "multiple demographics". Like Pretty Cure being for girls & Kamen Rider (& Super Sentai) being for boys. As opposed to making multiple franchises that can bring in money from both sides they think they have all their corners covered by having one franchise dedicated to each gender.

Now I'm no business major or expert, I'm just a dude typing on a phone. But, while it might not exactly be making half the money they could be, I think they could be making more if they didn't divide their potential audiences for their shows & toylines.

However, as I said before, they'd have to sacrifice potential immediate sales in order to gain significant sales much later on. It really boils down to short-term vs long-term. And short-term gain with segregated demographics is what's keeping them afloat right now. Unless their sales plummet for all their current franchises & drive them to do something "drastic" (make a Digimon leader a girl, make a Pretty Cure leader a boy, etc.) things will continue to be as they are.

Sorry if I rambled & didn't make much sense. I tend to do that. ^^;

I say, try to introduce more female side riders.
introduce them without having them take the spotlight.
then, when you've got the audience used to more female secondary riders, a female rider could work.

a male pretty cure leader is too much of a stretch. I've always had this idea of a character who could initiate the precure transformation for a while, and then is able to take on the enemies on the side without again, taking the spotlight (a tuxedo mask like character if you will)

Has little to do with equality and more to do with boys not buying girl toys same as in the West.

Shhhhh, don't tell anyone!

You can't expect boys to identify with girls because for god's sake, they are BOYS after all. It's natural to identify with characters of your own gender around a young age. That's why girls have shows like Pretty Cure and Sailor Moon and Boys have shows like Kamen Rider or Battle Spirits. And if girls feel like watching "boys shows" then they do. I've also preferred shows aimed at a female audience as a kid, but I've watched whatever I felt like in general.

And how is buying "male" merchandise a bad thing? Yes, there's still stupid parents that say: OMG, no, you can't buy that [girl name], that's for boys!- but honestly, most smart parents don't give a crap and buy whatever the kid is interested in. I preferred Barbie, but if I told my parents I'd want an Action man doll, they'd also have gotten me that one because they respected my taste. They even got me a doll they found ugly, just because I said I really wanted it.

Personally, from a female viewpoint, I don't think it is absolutely necessary to switch up gender roles to appeal to a broader target demographic. I always found it very refreshing to meet boys who love "girls shows" despite the shows being marketed as such and personally, I feel very at home in a fandom that consists mostly of males. While I would love to see more female riders, I am fine with the franchise as it is (despite being a bit angry when cool female riders are killed off. I'm still pissed about Marika. But I never cared much for Siren or Shuki, so I wasn't very emotional about their death aside from: Oh thank god, that b*tch is gone).
I never complained about having male leaders in Digimon, nor an all female hero team in Pretty Cure. I did complain about 90's anime Tuxedo Kamen in Sailor Moon because I really like the strong and cool guy he was in pretty much any other version and he wasn't in that one. But not because of his gender. I was annoyed that they ruined one of my favorite characters. Personally, I give a crap about the character's gender as long as I find him or her interesting.

This, pretty much.

Oh btw. Remember that female Ninja turle, Venus? Even girls hated her. Not because she was a girl, but because people disliked her role in the franchise.

I look at it like this: A female main Rider would pretty much be the equivalent of a female Batman,Prime,Spiderman or Iron Man in the West and just as unlikely to happen for the same reason I said earlier: execs think rightly or wrongly boys wouldn't support a heroine.

I mean heck there was a shitfest over a woman getting Thor's powers in the comics awhile ago and this is a demograph you'd think would like that kind of thing.

I think that's pretty much it. You associate a character (or the character's gender) with his/her powers, especially in a franchise. And rider protagonists or most riders in general are just associated with being male. Honestly, if the design doesn't have some very defining feminine features, such as Marika's pink suit or Shuki's skirt, it's sometimes hard to imagin a female in it. IXA is more neutral, but due to the white color, I tend to see it as a very feminine design (compared to, say, OOO or Wizard) and have trouble imagining Nago, Jirou and Otoya in the suit, while I have a hard time with Akiko and Kiriko briefly transforming into W and Drive. And the Mages in Wizard also look extremely masculine to me, even though Rinko and Mayu also use that form.

And well, Thor also has the problem that he was inspired by a male god and a exlusively male name doesn't help either xD

there's..... more to that than just "thor is now a girl?" in terms of why the comic is getting shit on. just lettin' you know.

Difference is, here we're suggesting a new season where the main rider simply is a woman, rather than retconing or replacing Bruce Wayne, Orion Pax, Peter Parker, or Tony Stark in their already developed roles with a woman, who takes their hero name (though why a woman would call her self BatMAN and not Batwoman would be odd, so really only Optimus Prime would work gender neutrally here).

The Thor situation is an entirely different thing of its own.

The reason there's a shitfest over Thor is because:
A.) the retcon they pulled to say Odinson was unworthy of his powers didn't even explain why, they just had Fury whisper in his ear and poof, no hammer for Thor,
B.) They haven't bothered to reveal who new Thor is yet, dragging out the mystery to make it seem more interesting (event though the whole point of Thor's hammer is worthiness, and if we can't be told who the new Thor is why should we just consider her "worthy"?"
C.) Crusher Creel, the Abosorbing Man, goes from a mostly neutral in regards to why he feels like attacking a Thor that day to becoming the writer's strawman for every person complaining about Lady Thor, because apparently the man who fell in love with and married a supervillainous who regularly brutalizes She-hulk would give a damn about who's wielding the hammer, and go on a rant about how she should get her own identity and blah blah.
C1.) Also, why the fuck would Titania spew some "girl power" nonsense and knock her man out over this? She's proud there's a female Thor? Again, where's this sisterhood when she's ambushing She-hulk? Changing character's attitudes to sell your story is nonsense.
D.) This is more of a personal thing, as I defend the use of superhero deaths in comics to a certain extant, but here's my problem with this story: Thor has recently been killed off twice. Once in the Ragnorok arc around the time of Avengers: Disassembled, and later during Fear Itself. Superhero deaths, to me, arent' about "Oh they'll be back eventually", but more of a "Great, now the one hero I was reading won't be around for a while. What am I supposed to read now?"

If the only X-men you liked was Nightcralwer, his death in Second Coming robbed you of a reason to continue reading X-men. If Nightwing is the only member of the Bat-clan you have an interest him, if DC was to suddenly cancel his series you'd have no way to get your Grayson fix.

Fans just recently lost Thor, twice over, and while the Tanarus arc was brief, we had no idea at the time that that would be the case, and the bullshit retcon where Tanarus had always been the Avenger thunderer gave some of us worry that this arc was going to last longer than it should (say maybe 2 years at most). Steve Rogers is still around, and we at least know Falcon and are aware of his right to be Cap just as much as any of Steve's allies. Steve didn't lose an arm when they depowered him, and with the way everyone is trying to recreate the Super-Soldier serum being a constant thing in the MU, it won't be long for Steve to be back in shape if they really wanted it to happen.

Removing Thor, not only from his power but his freaking first name (they Literally only call him Odinson now, which is demeaning to the character in so many ways) but most of his powers. Now he just has his axe they just introduced from his early adventures and a tattered red cape. Also he's missing an arm, so now has a...not a cyborg one, more of a magical metal replacement? That part confuses me, but still, at the end of the day they mutilated the original Thor, not even having the decency to just kill the character and leave him whole and with some respect for him intact (implying that he had some secret that made him not worthy, but not telling us leaves a future retcon open that will piss fans off more than anything happening now), and yet we're supposed to love new Thor why? Because Mjolnir flies for her better? Because she can make lighting curve and track her enemies instead of just blast forward or raining down (which is legitimately cool visually, but still)?

When Monica Rambeau briefly took the name Captain Marvel, or even now that Carol's taken the title, at least the original Kree was dead, and they didn't have to imply some fault with him while doing so.

I don't particularly mind new Thor, but there is too much "shut up and accept it" coming out of the writer's mouth for me to defend it.

This is a different case, though. Your comparison doesn't quite work.
Spider-Man, Batman, Optimus, etc are all established characters with histories and adventures. People aren't upset that they'd just become female, but that they'd usurp their titles and replace them.

This would be akin to watching Eiji as Kamen Rider OOO for 40 episodes, then in episode 41, Eiji dies and Hina becomes OOO for the remainder of the series. It's insulting to the people who liked Eiji (Insinuating that people only cared for the suit, not the one inside it).
Boys WILL support a super heroine. Yes, they tend to attract female readers, but don't believe what news articles are saying. Both men and women are reading the likes of Ms. Marvel, Batwoman, etc. But your issue doesn't take into mind the possibility of people disliking female versions of their favorite hero not because they have a vagina, but because it means something horrific has to happen to their favorite character in order for their title to be passed on to begin with.

Edit: Beaten to the punch by someone who explained it better :lol