I don't need a source to confidently say that a large majority of men on this planet would not refuse to be felt up by a woman as long as she's above average in looks in their opinion. You're telling me if a beautiful woman just walked up and felt you up you'd cry sexual assault? If you say yes you're part of a small minority or you're just a straight up liar. This double standard is engraved in our brains and our culture for so long that it'll take an extremely long time to reverse. So is it fair in the traditional sense? no, is it part of human nature? yes.

These things take time, you can't just say that if one can do it that the other can to and everything will be solved. First we need to desexualize breasts, that will take AT LEAST a hundred years or so if we started right now and put everything we got into raising awareness to the culture change. Wait for the last generation of people raised on jerking off to the mere idea of seeing a nipple to die off and only then will it be completely equal.