This is probably one of the most interesting and worthwhile, and actually relevant theory videos I have ever seen on a game.
It's definitely an interesting theory, and I can definitely see parts of it potentially panning out. Though in particular, I have an issue with the second point.
I don't think Phoenix Mode was a way to appeal to a
younger audience, but a
different audience: that audience being Visual Novel fans who play for the story and nothing more. And honestly most visual novel fans aren't young to begin with either. So in that regard, I don't see Fire Emblem ever getting to the point of a less-than-T rating.
Fully agree on the Deeprealms thing though; it seriously made zero sense.
I do disagree with the
degree in which censorship may affect it though: particularly, the example he used of eliminating entire chapters. That really doesn't seem like something Nintendo would do, as that's an incredibly bad practice. And honestly, it's kind of ironic he used Pokemon's lessening of maturity as an example when Black and White 2 straight up had the antagonist attempt to
murder you, and X and Y had the whole war from 3,000 years ago where it's explicitly stated that many humans
and Pokemon died in combat.
Over all, an interesting video, though I believe a few of the concerns are either unfounded or a bit exaggerated. Definitely food for thought though.