We need to nominate a dude to the mod team for the EXPRESS purpose of banning this weirdo's alts. I'm grateful to u/DomitiusofMassilia for popping in every few days, but sadly that's not frequent enough. We need a daily reader who can just hit "ban" when he's browsing comments. It won't solve the problem but it'll alleviate it.
We could also freeze new account creation and open it for select periods, announced with pinned posts. Our growth would be disrupted of course, but it's not like that matters that much.
This is my line of thinking, too. I probably spend far too much time a day on this board even though I'm not commenting as much as I used to, but it would be enough to play whack-a-mole with this spammer and any others if needed.
The only thing any new mods need done to help address the ongoing shitshow is to ban accounts. That's it. They don't need to pin new threads, edit any site features, or do any other number of things. It only needs a very precise, scalpel driven approach to excise this troll who clearly has nothing going on in his life to have so many accounts made in the first place.