Today I've been thinking about men's swimwear a bit. At the swimming pool I've noticed a quite striking contrast. While women's swimwear has liberalized over years in a such way that bikini (and monokini for that matter) for swimming are socially acceptable, the men's swimwear went through a regression. Many men wore trunks and sometimes even something even longer. While bikini make sense for suntanning, I can't exactly put my finger on this. Perhaps it's the convenience of not having a separate swimwear, but that's not really hygienic and I don't see swimming in trunks being quite comfortable enough.
As a cherry on top, for some men their trunks don't really fit and naked butts can be seen occasionally. This part is actually fun.