I really think that if people are going to ignore the opinions of female players regarding someone playing a male sexist character, then they don't really deserve to speak on the topic...
I think you've missed the part where, due to the nature of the sexism, people who aren't okay with what's going on usually don't say so. It's just my personal observation, but I find this to be
especially true in situations when there are women who express support/indifference for the subject at hand (for example, roleplayed sexism). Because that tends to lead to arguments along the lines of "Well, those women are okay with it, so the problem here is you."
Normally I wouldn't put myself into this kind of conversation, but the 'these women are okay with it so everyone should be" thing really irks me. You're obviously not trying to be offensive, but please recognize that different people have different levels of tolerance and sometimes the people who are the least okay with a given situation are the people you're
not hearing from.