You forgot
An update was recently released that didnt change the game in a way some long-term players wanted, and they're angry they fell for hype from streamers and are taking it out on the devs instead.
Or, as we recently saw in helldivers
An update was recently released with a bad translation, and gave players an expectation they could do something that they couldn't, and it became politicized
Some indie games only have a few hours of content. They don't want to get in a position where people can basically play complete indie games without the developers being paid for it.