People put on a false front with offensive messaging claiming support of these groups, but the whole purpose is to build clout or benefit themselves. They don't care about the message at all.
Messages like "I support lgbtq, and if you don't you're a bigot," are self-aggrandizement. "I support lgbtq," is all that's needed if you want people to know they are supported. No one needs to hear it at all if the discussion isn't relevant. Just try to treat everybody with respect.
But then literally in the same sentence, you say, "If you do the thing I don't like (in this case, calling people bigots because they don't support lgbtq) *then you are self-aggrandizing."
"Nobody should be called a bigot for their views on lgbtq, but it's virtuous to call people self-aggrandizing for calling people bigots."
Either name-calling is okay or it's not. You can't have it both ways.