There have been tensions between the FIDE organization and top players like Carlsen since the latter have been promoting an alternative chess organization around Freestyle chess (aka Chesss960), which has slightly different rules.
I.e. this is less about "dress code enforcement" and it is more about "Carlsen is fed up with the FIDE organization in general".
During Kasparov's era sentiment was similar and ultimately an entirely new players' association with their own world championship cycle was created. In the end they reunified with FIDE, but we're back on the trajectory for something like that to happen again.
I would wager alot that chess.com is strategizing behind the scenes about ways to become that replacement.
I think there'd be material there for an investigative journalist (if such a thing still exists to get out the old whiteboard and start figuring out connections and trying to piece together what might be going on behind the scenes. In any case, there's a lot of money involved.