Believe it or not, there's a lot of queer people who are pretty bigoted against other groups under the queer label. The classic example being LGBdroptheT. The affirmations of specific groups are a reaction to that in-community bigotry, which sociologists call lateral violence. These all-encompasing terms like gsrm don't always fulfil the function of explicitly including groups that suffer lateral violence.

There's even trans people on Lemmy who claim that nounself pronouns are a transphobic trolling tactic.