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.
Most instances are run by volunteers with voluntary donations for support. I prefer this model to the for-profit situation we’re more familiar with, but corporations usually have paid support staff on call. Some large Mastodon instances have minimal moderation. I think we will see outbreaks of ugliness as jerks test limits and find loopholes. 4chan is probably launching campaigns as I type. Hopefully the community rallies to beat them back, but good intentions alone do not suffice.
Would you mind sharing the server?
you can use https://instances.social to look for something that you think is suitable.
(big/small, specialist or not…)
https://mastodon.social is the biggest /most general, and kind of the default for many.
bare in mind, you can later migrate to a different instance, so you dont need to fret too much.
edit: above comment assumes you don’t go for an instance with a small user base that could possibly one day just ‘disappear’… remember anyone can setup a server.
The server I chose was mstdn.social. The admin is @stux, and he has a pinned post talking about himself and the site. There are currently about 125K users on it.
Appears to not be allowing new accounts at this time. 180k users. Trying to find a sort of generic server with decent population that doesn’t risk folding. Lots to choose from though. 
Same guy’s overflow server is masto.ai.