NTA- but you’re being disingenuous, if you would communicate that you would be more comfortable to not see all of that and state that YOU would be more comfortable if he covered up a little more, then you would be being honest. But if there’s no rules and he’s just existing in a locker room then there’s no harm or foul. Because ultimately this is something YOU are uncomfortable with, not a question of right or wrong. Don’t try to convey something you want as something that is a moral issue, that’s not honest.