My 6th grade teacher did exactly this, but went beyond normal nicknames and said if there’s ANYTHING you want to be called she would use that name instead. Granted, every teacher before that would hear the nicknames and just use them anyway, but this one went a step beyond that.

Not a single kid used their birth name. Some used regular nicknames, some used their parents nickname for them, and some chose something else. I went the cringier route and chose “silent hill because I like that game and I’m usually quiet” and sure enough she called me that all year. Had the nicknames down by the end of the week and still knew each child’s real name for when she’s talking to other adults.

I don’t see what the big deal is with using someone’s preferred name. Legitimately the only reason to not use it in this context is to be a piece of shit.