I think the difference between the Oscars and the Grammys is that a certain type of film almost invariably wins the Oscars, but the Grammys are all over the place. So on those rare occasions when the Oscars buck historical trends, some people do kinda lose their shit. Those picks were contentious, but there weren't many filmmakers still screaming about them 2-3 years down the line. Damien Chazelle isn't refusing to submit La La Land to the Oscars because Brokeback Mountain didn't win.
The Grammys are historically all over the map, much more so than the Oscars. So I don't feel like people should take the loss quite so hard. In the last couple decades they've given top awards to all kinds of weird dark horses -- O Brother, Norah Jones, Robert Planet/Allison Krauss, Beck, Herbie friggin' Hancock, etc. The idea that a top-selling album in a culturally relevant genre is more entitled to win is kind of silly, given the precedence.