I've seen a lot of post claiming that "If you don't like Dynasty Warriors, you won't like this game." Frankly, I think that's only half the problem. I think it's also true that you probably won't like this game (and, in fact, will probably be actively repelled by it) if you don't like fanservice for fanservice's sake. Much like how Star Trek: Generations was an objectively terrible movie that Star Trek fans loved because it featured Kirk and Picard IN THE SAME MOVIE!!!~1!, Hyrule Warriors is a game which has nothing much to recommend it save for the fact that it has Zelda characters plastered on it. Seriously, Dynasty Warrior fans, I want you to answer me this question honestly: In the absence of the Zelda characters, was this game really the best expression of the "_____ Warriors" subgenre? Or even a terribly good one? Mario Kart, Nintendo-fanservice aside, is a really good racing game. Smash Brothers is, at worst, a very competent fighting game. Hyrule Warriors is a mediocre example of a genre game, and a genre that most of the people playing Hyrule Warriors would never touch if it didn't have Link plastered on the cover. They are, essentially, buying a game because it has Zelda stickers on it, not because of the game that it is. If this game had been released as, say "Fantasy Warriors", with the same mechanics, story, and gameplay, but without the Zelda characters, it would have come out to a bunch of middling reviews, sold a few copies, and been quickly forgotten by all but a niche audience. And as a critic, the fact that an otherwise pedestrian game can be elevated to must-own status for a lot of people just by slapping the right stickers on it must be galling. That the stickers in question are Zelda stickers, a franchise that for some reason is given more passes than exist in a season of football games, is just icing on the cake.
And people are on here complaining about Yahtzee insulting the fanbase? I'm sorry, is this the first Zeropunctuation video you've ever watched? If it is, this series is probably not for you. If it isn't, then you're the person at the comedy club who laughs hysterically while the comedian mocks everyone else in the crowd, only to turn sullen and red-faced when they say something mean about you. Seriously, don't be that guy. "It's funny until someone does it to me" is a terrible attitude to have towards... well, anything, really.
EDIT: Just to be clear, I actually quite like the Zelda series of games. I think those who recall Ocarina of Time and Majora's Mask as among the greatest games of all time are viewing things through rose-colored glasses, but Link to the Past, Wind Waker, and Twilight Princess are some of my favorite games. I do think that people are more willing to give a Zelda game a pass for any flaws it may have than they do other series that might make similar errors, mostly for sentimental reasons.