@aydingerek

Great question, many possible answers!

Each server is totally independent, each decides for itself what is acceptable behaviour. If you go to a server's about page it has that server's rules.

Another is what kind of people use the server, as this determines server's Local timeline (on the official app this is found by pressing 🔍 and then Community).

If a server is badly run with no moderation, it will be blocked by other servers.

...there's more but don't want to complicate! 😁