Maybe I am not understanding the fedivers well enough, but why am I not seeing communities like !flippanarchy@lemmy.dbzer0.com from my europe.pub account?
The instances seem to be federated.
Edit: they are accessible when using a direct link like the one in the first paragraph, but the search function doesn’t seem to work.
A lot of instances de*federated, so you have to subscribe or join a different instance. Try this, idk if it lists every instance, hopefully csam ones are not listed
https://lemmyverse.net/communities