Communities are all about, "Either go along with our particular cult doctrine, or get out."
But this kind of mentality is also practiced by the infrastructure providers these communities depend on; a subculture can get cancelled for not going along with the superculture.
The result is that cultural innovation often gets strangled in the cradle.
There was a debate recently on a libertarian Telegram group about whether the world is overpopulated or underpopulated. Some people were saying that humans are destroying the biological diversity of the earth. A counter-argument I mentioned is that if other species on the earth are going to survive, they'll probably need to hitch a ride with humans to some other planet. E.g., we might bring cows, or bees, or whatever else we need for food.
Anyway, SJWs talk about how they're preserving cultural and racial diversity, as well as the equal rights of all, by getting rid of intolerance; but in order to do that, they have to destroy a lot of subcultures that might go counter to their agenda. A lot of those subcultures are rather beautiful and maybe even useful; for example, the Nazis were renowned for their aesthetics and technology, even if some might say, the potential of a generation of Hungarian Jews was curtailed by the Holocaust.
What's the effect of all the deplatforming that's gone on? Well, I think it tends to produce a more militant attitude on the part of the deplatformed. They hate the deplatformers more, and become more determined to be cultlike and not entertain opposing viewpoints with as much of an open mind, because they regard them as more of a threat.
If antis don't get treated well on girllover boards, it's probably because antis have a history of shutting down these boards, and it's made people not like having them around. If you want to be allowed to speak freely, you have to extend that same privilege to others; otherwise, people are going to lose faith in the sincerity of your stated intentions to argue in good faith and to search for truth with an open mind.
What the censors are hoping is going to happen is that they can coerce communities into self-censoring for the sake of being allowed to enjoy the privilege of continuing to operate at all. That does happen sometimes, but it doesn't always play out that way.
Sometimes, they just end up radicalizing people. People take a more extreme stance, viewing it as necessary and justified to counter the type of people who want to censor others.