How did the discussion on 2FA suddenly change to moderation again? They are quite distinctly different, and no neither needs to be changed.
I've been banning idiots since the 80s and it's still exactly the same motives. Spam and new or sleeper nuisance/troll users should have posts removed or hidden if possible as it's their agenda to permanently taint the forum. If you want to get rid of them long term though there are ways of doing that as well.
However, it's not the end of the world to let them come back and contribute to the forums ad revenue until they raise the alarm again. The more they do this the more helpful it is building up a dossier of services to block that identifies other nuisance users at the same time, aka honeypot.
If they remain loyal haters and pitch in, let them waste their life. But I mean coming back to Dave for this long seems like there might be some underlying sexual reasons, not that it's bad to sexually express yourself but Daves happily married and i think the chance of a hater hookup is pretty low at this point. Sometimes you have to take it on the chin, cut your losses and move on and find love elsewhere.
As I mentioned Dave/Simon if you don't like the word "banned" you can use a more friendly word that is understandable to all users.