I'd wager the complaints of the sort of people who frequent lobste.rs or HN are not representative of the majority of current users and almost certainly not of the next 6B potential users.
Overall, it's everything Google said they would do with material [1].
It's fine to dislike these things, I don't necessarily like them myself, but claiming they're simply wrong or "for no reason" is somewhere between angry and lazy.
Just a glance at the new vs old keyboard or gmail shows a direction - moving / duplicating interactions toward the bottom right (logical as screens get bigger), breaking out punctuation into discrete keys (presumably logical given the way most people actually type).
The overall restyling is adding consistency between apps and particularly between mobile and the desktop.
Animations are really valuable anytime someone doesn't come to the table with a complete mental model of how something fits together already. Basically, they're not for you Mr. Programmer.