The why part is easy. Women can make anything or even nothing at all look sexy. Women can even dress in mens clothing and look GOOD. Guys put on women's clothing and unless we are performers and supposed to be doing it, we look pretty weird. Guys can wear pink, but it probably aught to be a shirt. Pink pants looks rediculous on any guy let alone a skirt or thong.
For public, a man wearing clothing that is pink is weird because females use pink stuff a lot more than men. So most people think that "Pink" is a female's color. But that doesn't make sense, any man can use any clothing with any color! The men should not care about other people and what they think about what color they wear!