It seems the main complaint here is not actually of sexist males, but of people who cannot separate fantasy from reality.
At the end of the day, I doubt that most players step back from their computer screen (or couch potatoes from their televisions, or bookworms from their novels) and think to themselves, "Well, that was fun, but it wasn't real."
From what I've seen, most people can. Usually people learn that fantasies aren't real by pre-teen-hood and begin treating them as such: escapes that don't actually affect their lives besides providing entertainment and stress relief.
Those who can't, who let fantasies become part of their life as if they're real and apply them to the rest of the world, most likely have not grown up yet, have not had necessary life experiences, and/or are a little bit off in the head. The people who are most complained about here for being sexist towards women are, ding ding ding- sheltered nerd men who have most likely not had much social experience, so they take cues from what they've seen through fantasies.
If they let their fandom define their life and believe real life should be like in their entertainment they will most likey not act appropriately. That is the person's problem, not the game's problem. It's bad parenting in most cases- parents let the TV do the parenting, so the child takes cues from the entertainment.
No one was there to suggest "Son, this stuff isn't real. It's just for fun, nothing like that happens in real life. Real people are not like this." ect. Feel free to disagree, but I've noticed people who have more attentive (yet not overly sheltering) parents seem to be able to separate fantasy from reality.
There ARE nasty people out there of both genders who go so far as to treat people inhumanely due to not being able to identify with reality, and unfortunately a lot of them are so far gone it's nearly impossible to bring them to reason. (If you're not too squeamish and of age I suggest reading /cgl/'s cosplay horror stories... plenty of proof there...) But it's not fair to judge the majority of people like this. Most people are sane, the reason there's so many more negative experiences is because negative experiences tend to be more emotionally stirring; people love to share what awful things happen to them.
TL;DR: If you're mature enough to know what's a fantasy and what's reality, you will most likely not become sexist due to entertainment. There are plenty of people who are not mature enough to separate them that cause problems, but most normal people will not become so irrational due to some 3D boobies or gorey hack-slash movies.