I've got a weights bench set up in my "Mancave" garage and naked workouts are my default. Typically a few three minute bouts of punchbag and speedbag work with skipping followed by free weights. I've no problem with my dong flying allover the place when I'm skipping or doing bag work but I hate the bar touching my dick when I'm deadlifting. Dunno why it just sets my teeth on edge, so I jock up for that.
There used to be a gay sauna (Bathhouse) near Liverpool St station in London which had a gym where naked weight training was the unwritten rule. It was never busy but ther'd usually be a couple of nude dudes benching or on the flies. I always started a visit there with a workout to get a T spike before cruising. It probably sounds like orgy central but I never saw any "Action" in that room, it felt like it was being used by guy's who didn't bullshit when they hit the gym, they were there to workout and then they'd just fuck elsewhere in the venue rather than have a sneaky wank in the showers like you might at a ordinary gym.