It is NOT the other way around.

He chose to enter a tournament whose organizers impose a dress code, without complying with the dress code.

The dress code is silly perhaps and has nothing to do with chess. But if he didn’t like it, all he had to do is not participate.

I know fellow pool players who regularly forgo some venues on the circuit because they’re forced to dress in a certain way that’s to restrictive to movements around the table in their eyes and that’s fine. Their tournament, their rules.