If someone is banned from a channel (not blocked) they should not be able to follow the channel. This should help limit the amount of bot spam and harassment attacks by making bad actors not be able trigger alerts or flood channels with follow bots.

Another option would be to have an option to block banned channels automatically and having ban apeals as a separate form rather than just messaging the channel.

It is beyond frustrating to get 20+ bots follow you in half an hour each with a simular name, some with blantant slurs.