I can understand his frustration with Nintendo's youtube program. Having a cut of your profits given to Nintendo for using any of their assets isn't great and it's free advertising for Nintendo, but there is a point to be made for Nintendo's actions: spoilers. I recall Sakurai stating this being a reason why he did away with the story cutscenes in Smash Bros, as people quickly posted these online and allowed people to watch them without discovering them in-game themselves. It's not a great reason, but it's one, and I think understandable.
Besides, if he really wanted to talk about BotW or any other game, I'm sure he could find a way without using any assets. Also, despite what he says, other youtubers don't seem to mind much, as I've seen reviews from several others already.
Dance my pretties!
The Official Art Thread - The Official Manga Thread - The Official Starbound Thread
