[Matrixbeast]

And what difference does that make?
No complete dex of Pokemon has ever been available in one game.
What if Sw/Sh had a full national dex, but there was no method to obtain, say, any Gen 5 Pokemon? There was no method to transfer them across, there was no area in the game where they would appear, and no trainers offered them for trade.

There would be literally no possible way to get any of the 151 Unova Pokemon, even if their data was present.

Then what? We don't know if they would make them available. Kalos came and went, with the "Obvious" Z version never showing up, so it's not like Pokemon is predictable even when the clear pattern is present. So just because a national dex would be in the game, doesn't mean they would have any intention of shoveling all 900 critters into it.

Which would be better? Having hope that characters might become available down the line, with absolutely no promise or even hinting towards them even doing so, or just knowing what your options are from the get go?

This issue is just where the line has to be drawn for by the devs. My all time favorite Pokemon is currently Primarina. A starter. Unless it's X/Y giving you a Kanto starter for free, you only get one, and unless there's some post game content that allows it, that's your lot. Primarina isn't going to be in Sw/Sh. And even with a nat dex, she wouldn't become available unless there's some stupid ass gamestop event. How do you think I feel, knowing that my current all time favorite Pokemon will never be available for some time, and a national dex won't change that? I'm shit out of luck regardless.

We all can't get what we want, but battering down Gamefreak's social media and attacking them on all fronts comes across as the most petty and entitled this fanbase has ever been. Pokemon is just trying to be fun, and if I can come to grips with never seeing my favorite Pokemon again, then I'm sure you lot can handle perhaps learning to love other Pokemon, too.