As an example, that one will ban extreme (and not so extreme) right-wingers. But you also have the opposite in other servers. And of course those servers refuse to federate with others. So there obviously are no flame wars like on Twitter... All ideologies are separated.
The reason there are no flame wars is not that Mastodon users are somewhat enlightened, as opposed to the Twitter rabble. Instead, clashes are avoided by having (and enforcing) rules and banning ideologies. The catch here is that this would never scale; this only works because there are only a few users.
I tried following https://pl.smuglo.li/users/roka (an anti-Semite who posts porn) and got a nondescript error. How can I tell if this is due to a blacklist, and if so, if it's on my instance or theirs?
In any case, you should contact the admins of your instance, but most probably they have blocked that instance, as it appears on blocklists for being a free speech zone.
https://pl.smuglo.li/notice/5986711 is pretty vicious antisemitism. Apparently I have succeeded in following this person now though. I'll see if I end up seeing their posts.
The reason there are no flame wars is not that Mastodon users are somewhat enlightened, as opposed to the Twitter rabble. Instead, clashes are avoided by having (and enforcing) rules and banning ideologies. The catch here is that this would never scale; this only works because there are only a few users.