Modlog, which includes a site ban—something only admins can do.
The community bans also include communities that aren’t moderated by any instance admins, and some that are only moderated by a single person who likely isn’t aware of actions taken under their community’s name.
My bad. Iäm not saying that lemmy.ml is acting in bad faith, their Rule 2 looks very much like a catch-all for anything they do not like. But the user in question could have used better wording.
20 community bans is indeed not warranted.