Fair enough, but one can justify racism and ethnocentrism by appealing to our animal instincts as well – we may very well be predisposed to seeking power over others and reserving trust for those we perceive to be our own kind. Now granted, I have no way of proving that there isn't some kind of misogyny gene. But legally, slavery was done away with by passing a constitutional amendment that makes no direct reference to race. Culturally, there was a large precedent of underground and increasingly popular outrage against the practice, founded in principles of human equality that had to be actively argued for.
I bring up the parallel, again, not because it's an equivalent situation, but to illustrate what I think is a common ethical trap we can fall into: what good is it to see an injustice and wave our hands, saying that it's just the way the things are?
You suggested that the grandposter is blindly optimistic for wanting to change the way men relate to women in the workplace (or something like that), but think about how much has changed culturally, that we can have this conversation in 2010 and have it be basically a given that human bondage is morally wrong? It took a law in 1865, and it was controversial at the time. Today you have to be on the fringe of society in order to believe that it was ever morally defensible, presumably. That's not a triumph of law, it's a triumph of active social change.