The biggest issue is that this is not really an issue of gender politics.
It's all about toy sales. It will always be about toy sales.
And when the toys of the female characters are cited as being worse than their fellow characters, then they won't get the prominent role people want them to hold.

The simple counterargument is typically "Then add more female characters. The numbers are so low because there's so few female characters to begin with." But that's not a real solution. Boys want to project themselves onto the main hero, which is a difficult issue when they don't even share a gender (Note: Difficult, but not impossible). (Most) Children aren't watching Kamen Rider for the deep, intricate story (Despite what most Gaim fanatics will try to tell you), but just for escapism and to project themselves onto their favorite heroes. By severing that link or making it much harder to connect just for the sake of a weak attempt at equality isn't worth the risks.

the difference between those cartoon and Kamen Rider, is that theres over 35 years of history with male heroes, and one of the others started with the female cast from the start, and Korra was still in the same universe, and many of the fans of Korra watching it were people who grew up watching the first airbender.

and even then, Korra was taken off the air for the third season because of low viewership.

You forget however, that those toy sales and salesmen are still dictated by these politics, which then, goes back to my previous arguement about the issues of blaming kids for something that is created by adults.

I'm not sure how the former exactly causes conflicts with what I'm saying, and I was mostly talking about the boys' initial reaction to Korra and how easily they accepted her. The show's eventual outcome has more to do with general management more than anything.

if a kid doesn't want the toy of the hero, it's not the kid's fault, it's the show's fault. I don't anyone is blaming kids for a show not succeeding in toy sales.

Exactly. Kids will like characters if the show does a good job at it.

But unfortunately, reality is toymakers are satisfied only with the bare minimum.

it was already established that the avatar could be male or female in the last airbender from episode 3, so there was little to no nonacceptance of Korra being female in the first place.

like I said with Kamen Rider, it has a lot of years where the males were the lead, and it grew to have a large fanbase of young males.

BUT at the same time, alienation of one part of your audience solely to draw in another can also account of failure.

I think you are forgetting kids don't have the same amount of acceptance to the idea of canon as adults have.

I doubt any kid actually praised Korra for being the natural extension of the fictional rules of a fictional universe they would most likely are not that aware of.

But like I said before; kids are not that stubborn.

Now I'm not saying that everything can just be changed willy-nilly, because realistically of course suddenly having a female main Rider immediately is impossible and Toei's infamous pig-headed attitude is all too familiar to us by now, but I'm saying kids should not be blamed for a system completely outside of their control.

No, they're not.
Toy sales are dictated by one thing, toy sale. And as redundant as it sounds, it's true.
Kids aren't to be blamed by what they do or don't buy. In all actuality, it's the adults who follow what trends the children are into and want.

It's a very circular cycle, but you're trying to pin the blame on the adults with the argument that they "Instill these values into our children" when it's not always the case.

Korra is actually a rather weak argument, as it alienated older fans and younger fans were rather uninterested with the weak ratings the series received.

Yes.

Yes it kinda is. Kids don't exist in a bubble.
My arguement had nothing to do with what happened to Korra afterwards. I was strictly speaking in terms of how the character was received initially.

What happened later is far more complicated.

Actually, they are.
After all, we're talking about a franchise originating from a country infamous for it's desire for rebelling against the system, for it's want to change the norm.
However, when it comes to fantasy mediums, kids will always be kids. When you present a viking man and an amazon woman to a little boy, they'd be more likely to gravitate towards the male, not because of the system, but because they can see more of themselves in the character they share the gender with. They can simply just identify easier.