I have been a regular at a gym on a university campus for the past 3 years and I’m happy to report that, at least at this school, young guys aren’t afraid to get naked in the locker room. It was only last summer that they set up dividers in the showers, which had been communal since the gym was built in the late 70s. I’ve seen some both the largest and smallest dicks in my life in that shower, and you have the full gamut of everything: cut, uncut, shaved, natural, girthy, slender, huge balls, etc. I’ve seen 5’5 guys packing more meet than 6’5 basketball players. I’ve seen an African American guy who was at least 7.5” limp. I’ve seen a Jamaican guy with the shiniest, pink glans that contrasted beautifully against his black skin when he pulled back his foreskin. I’ve seen a guy who’s friends’ bodies looked like they were sculpted by the gods and had nice shaved tools between their legs, while you could only make out his very small glans poking out from a massive mound of black pubic hair.
I think a lot of different factors are at play, with the setting and clientele being two prominent factors. At 30, I am one of the older patrons at the time I go (every morning between 7-9 am, though there are a few much older guys here and there). During this time of morning, we’re a small crowd (about 25 guys) and we all know/of each other as regulars. For myself included, I think it’s helpful to see that the guys you see in the locker room are also the same ones putting in work on the gym floor. I’ll be the first to admit that I also enjoy checking out other guys’ bodies, but we can all tell when someone is just a shower/locker room hawk who comes in for the sole purpose of checking out other guys and maybe looking for action: You never saw them actually working out. I also avoid changing around these types.
There have been plenty of guys who would be extremely modest in the locker room, and then after a week or so of noticing me moving about naked, changing sans towel, and sitting in the sauna in the buff, they would start to follow suit. I’ve even seen guys come to the sauna in their briefs then once they saw me there naked, they would go back to their lockers, take them off, and come and sit completely naked with me. But also I’ve noticed that in general, the college age guys are more modest around their friends. You see the towel dance more frequently, but when they are alone, they do things naturally.
It’s unfortunate but I think the reality is that a lot of young guys do have the perception that
some older guys in the locker room are “pervy”, so they are more modest around them. Of course there are also younger guys who are pervy as well (at my gym, I can readily identify two who, as I pointed out above, you never see on the gym floor, are out of shape, and do the sauna-shower-sauna-shower circuit for literally over an hour).
Also, it’s important to remember that my generation was raised by the generation before us and the values they imparted. So the real question about where this prudish and fear of nudity became more prominent needs to be directed to the late baby boomers and early gen X-ers who raised us, not millennials and gen Z-ers.