That’s fair enough. But it is true that it’s very hard to harass someone, or a whole class of people, by nature of the design of the system.
But yes, if every mastodon server was run by fascists, to take an example, it would probably be a pretty nasty place for a bunch of people. But if as much as say 10% were run by fascists, they would pretty quickly find themselves isolated from the non-fascists to the point where it looked like they didn’t exist at all to those of a non-fascist persuasion.