the thing about fandom blowhards is that sometimes they're generally right about things, but so obnoxious that people get mad at them and disagree with them on principle.
so if you try to be a good internet citizen and just block and ignore them, at some point you will miss the memo on why everyone is really annoyed by specific headcanons. or even worse, you're a new fan of the thing and you don't know anyone's history.
like (to completely make up an example bc I don't want this to be about anything specific) maybe I like to headcanon a character as bisexual, bc as someone who is bisexual I think it's fun and sexy to be bi. and because I blocked them two years ago I don't know that Fandom Blowhard has been running around telling people they MUST headcanon character X as bisexual and anything else is WRONG because "one time she dated a man and now she dates women so she must be bisexual, it's like you didn't even watch the show oh my god people are so biphobic." and when people politely tried to tell this person why that's a shitty reason to insist a character is bisexual (comphet exists!), Fandom Blowhard wrote thousands of words doubling down and accusing everyone of having secret biphobic motives, hating character X, and being bullies.
and then either A) an old fan with a curated blocklist who has been kept blissfully unaware of sexuality discourse or B) a new fan pipes up to say "yeah I like to think of character X as bisexual!" and a bunch of people get really suspicious of them, or take what they're saying in bad faith, or outright get mad at them. which is! baffling and upsetting!
and A might be able to check in with fandom friends to figure out what the hell is going on, or just throw up their hands and leave the fandom. which is a huge shame because ideally polarization would not completely ruin the ability to talk about anything. but B is probably going to be approached by Fandom Blowhard who tells them "yeah this fandom has a HUGE biphobia problem, don't trust anyone" and then experience what is essentially a radicalization pipeline but about bi headcanons.
unfortunately as far as I know there are no effective solutions to this because it's an emergent behavior of large groups of people. there will always be Fandom Blowhards and people annoyed by fandom blowhards. the rest of us might just be stuck in the middle.
but it is why I try to approach people in good faith, personally. or avoid them if I don't think I can approach in good faith. and it's why I block/mute as much as I do, because seeing too much stuff that annoys you can fry your brain and make you lash out at people who don't deserve it.
