My 2018 GT has been making that worm shaft noise since after six months of buying the car. It's a common complaint, I'm seeing this TSB for the first time which is great news. I dreaded taking it to the Dealer only to get the run around that 'its normal" Good time to ask the Dealer to update the firmware and Maps on the infotainment system as well.
Had my steering column replaced under warranty for that issue. No problems, run around, or headaches.
They said they’d been replacing clock springs, and solving the issue temporarily, but the column assembly has been updated, and that fix has held up so far.
So how much would it end up being if that actually could figure out how to fix it. Also saw another article on this. Someone said that Hyundai will issue a recall over this, but that was 4 months ago, and I don't know if they really will. Don't know if I wanna risk going to the dealer just to get a call saying "they haven't found anything and it's just normal behavior". But if anyone else is gonna get theirs fixed, I'd make sure that the mechanics know how to fix it before taking it in.