In defense of temp bans: sometimes people will learn from their past mistakes so starting with a temp ban is a decent idea rather than just jumping to a permanent one.
Of course on Lemmy you don’t get notifications when you get banned, so it’s not as effective of a tool as it could be. Hell you don’t even get notifications of a comment being removed.
Edit: Banning in general on Lemmy is broken IMO. If you’re from a different instance and you get banned you see no difference in your day to day interaction in the other instance. You can still post and comment, it’s just on the other instance you are banned from the people on that instance don’t see that content. Couple that with the lack of notifications when you get banned or your comments get removed and people won’t know that their behavior is unacceptable and they won’t change.