Oddbean new post about login | logout Technically you should be able to just publish to your own relay in the worst case and people who follow you and whoever they share your posts with would still be able to read you with no issue.
What would happen if I comment under a post from an account that I neither follow nor that follows me? Would I still be visible as a banned user? Or to other users who also commented there?
if all the network were to reject you, no.. but that is on you... rejection and censorship are different
It depends on the relays that person each person is listening to. Your client decides the relays it will publish a comment to at the time you're posting. A sensible decision is to publish to your own "outbox" relays and to the "inbox" relays of people you're tagging. If the people you're tagging is only using inbox relays that have banned you then they probably won't see your comment by default.
If it becomes known that some relays are notorious for banning people clients may decide to implement some alternative heuristics, like (this is just a crazy idea that just came to my mind and I'm sure there are better solutions) if stupidrelay.com starts censoring a lot of people then someone may create a not-stupidrelay.com and every time one would publish to or read from stupidrelay.com they also do it for not-stupidrelay.com, I don't know.
I also think clients should have easy toggles for switching between comment sections by niche relays ("ok, I see what this guy's bitcoiner friends are saying, now let me see what his enemies monero guys are saying about the same thing by connecting to the set of monero-loving relays") and other stuff. Nostr is still too small for these cool thing to be viable though (and also too small for people to be banned too much), but I think we'll get there.