Most niches dont have to self censor. Even the ones that do still have no trouble communicating their message. I follow a lot of military channels and they post uncensored versions of their videos off yt but there is little reason to go because seeing the gore is not why im watching the video. I still get the entire value of the video from youtube even though you might argue its self censoring.
There's a lot of people who want to talk about things like Gaza or Luigi Mangione more, but can't because of platform rules. The new web has been successful at changing society at large by preventing discussion of these things. Even here on HN I have to be careful how I describe this effect, because an account that is flagged a few times in quick succession is automatically rate-limited, which is effectively a ban.
Edit: it's not just about a niche being forced to censor, it's also about everyone being forced to censor talk about that niche. In a video games discord you couldn't talk about piracy, no matter what the owner thinks about piracy, he'd be forced to ban you for talking about piracy or else he would be banned.
There is plenty of discussion on Gaza or Luigi. If you find youself being "censored" consider that your views and "solutions" are far outside what is accepted on the platform. On the old web you could also get banned if your views did not align with the platform.
Dont compare wanting a pro terrorism fourm with niche interests its so disingenuous.