This seems to be random. These are communities on the instance I’m logged into. AFAICT I’m not being blocked in these communities. I’m not even sure if mods *can *block someone from seeing a community. I’m guessing this has been asked before, but I couldn’t find a thread on it.
Shadow ban is different though. You can still post and interact but no one else sees you.
lemmy is fully open source (and other activitypub implementations), are shadow bans even a thing?