Man, we needed reviewers to review this game professionally and equitably for the game to do well, and they really blew it. 1-2 hours on the easiest difficulty isn't enough to understand the game (or to get the brain to make the transition from the abstract cues they are used to in other rhythm games to 3D animated characters as cues), yet that's all that the large majority of reviewers giving negative reviews played it. And unfortunately, most of the positive reviews aren't on Metacritic, and most of the negative ones are.
And so instead of giving the game credit for innovating in visual feedback in a rhythm game, they criticized it for not being a fighting game (seriously, IGN) or for the visual feedback being too noisy for them to handle. Well, yeah, it's a rhythm game that adds visual noise to the information signal just like every other type of video game does. That's going to make it harder at first, just like it would be hard to play Madden if every football game you'd played up to that point used nothing but 2D Xs and Os for the players. That doesn't mean that Madden's inferior; quite the opposite. You just need to play enough for it to click - which means EXTRA time playing the game for your review, rather than less time.
And the soundtrack criticisms don't square with how other indie music games are judged. Games with generic electronica, j-pop, etc. and shorter soundtracks have no complaints from reviewers, yet for some reason they obsess about the 4 or so older songs in the game and go on endlessly about how anything older than 5 years can't be used in a game because it's old. What.
So frustrating. Reviewers should be smart enough to understand this, but it's mostly just a bunch of derping from people who obviously wanted to be playing GTA V instead.