I used to belong to a "Natural Club/Nudist Camp" in the 1990. In the summer time, there were a lot of couples sitting around the hot tub. I never found anyone really compares their size, or length or paid any attention to check out the male genitali (but everyone check out the new chicks !! LOL)
Except for a few occasions when young couples sitting on the far side of the hot tub and making out, we might have pay attention of the girls' tits and hair, no one really cared about the guys.
I still remembered one guy showing up with two or three girls and making out next to the pool, my ex- was more interested to talk to the girls and no one paid any attention to his genitals.
It is not an issue. Most men in our club did not like "men to show off" rather they prefer men to get along together and share their babes !
Also one of my ex- used to go to downtown "swing club", she told me no one cared about "big dicks" because most girls were really not into big dicks because they "hurted" ! LOL !