There's something to be said for not shutting down someone unless they break a law. I do acknowledge the court would need to be much faster and easier to access for these kinds of things though, you don't want to burden a provider with enormous legal bills just to deal with this kind of thing.
If I host a service for manchester city fans, why would I not be able to ban annoying united fans? Who cares if what they do is legal. What if I post NSFW content here on hn. It's not illegal so it's okay?
Just this month content creators from Russia or belarus have been banned from dozen of services, they did not violate any law.
It's ridiculous to think that yout platform isn't free to apply it's own rules.
We're talking about platforms that are not so restrictive in their topics.
Unless you can prove in a court of law you're being restricted for illegal reasons, there's not much you can do.
Internet is full of stories of people losing their livehood overnight in these services and there isn't much one can do.