I've known several straight women who absolutely refuse to date bisexual men, or any man that has shown any bisexual tendencies.
I don't know any guys who would refuse to date a woman just because she's had sex with a woman at some point in the past.
Enough women either refuse to date bisexual men or say things like "Well, maybe if they like girls more than boys". I met a bi independent brand designer in Portland whom relayed rather humorous stories of liberal, straight women's discomfort with his bisexuality.
Then there's the sect of women who'll suggest a man is gay as a insult, but when rebuked will play a rhetorical game like "What's wrong with being gay?"
I once went on a date with a data scientist and when I told her I was interested in getting a cat, either to be provocative or accidently revealing herself, she loudly proclaimed "That's gaaaaay" in the middle of a restaurent. When I confronted her the next day about this statement, she said things like "I have gay friends", etc.
This notion that liberal women are absolutely receptive to queer men or anything they perceive as effeminate in men has real limits that are not actively investigated, and it has nothing to do with a subjectifying male gaze.
What evidence do you base this on? Women's attitudes have a big effect on social norms, so we certainly can't dismiss them out of hand. And women who seem to have negative attitudes towards male homosexuals obviously exist.
Granted I'm basing this solely on my experience having grown up a heterosexual man, but that explanation seems absurd. By and large, it has not been the women who have been intolerant of homosexual men, but rather other men.