As 50% of the population, all other things being equal, we should expect to see either total equality throughout history, or a flip-flopping of power between men and women. But we don't see that, we see endless patriarchy. Why? Because all other things are not equal. There has to be something to explain how men have been able to systematically oppress and exploit women, and what other explanation can there be than biology? Comparative physical weakness primarily.
It's not just a numbers game, for example when you look at the occupation of India, there was about one white man for every fifty Indian men and the India population were still oppressed. That had no biological basis. It didn't even have any technological basis, fifty India men could overwhelm a white man with a gun.
However, they didn't because they were cowered.
There has to be something to explain how men have been able to systematically oppress and exploit women, and what other explanation can there be than biology? Comparative physical weakness primarily.
Physical weakness is something that is experienced on an individual level. We have no evidence that men and women have ever fought each other in groups, no one-on-one combat. We've all seen enough Buffy to know that a number of small women can take out a large, violent man. but most women are too cowered to even try this.
Actual violent events between men and women are relatively rare in contemporary western cultures, while we all know women who have been attacked, the overwhelming majority of women aren't subjected to physical violence the overwhelming majority of the time.
While violence as it relates to physical size/biology is a tool of the patriarchy, it's not the defining characteristic. We have to recognise, as unpalatable as it is, that women have had a role in proping up this system. Foot binding, FGM, Menstruation Huts, etc. are all, traditionally overseen by women. They are not violent acts carried out by men and I can't see what value they would have to male society. It could be argued that the mikvah bath, taken by Jewish women to ritually clean themselves, is to the detriment of men, as it makes their partner sexually unavailable for almost half the month.
Women have colluded in the patriarchy and the blind insistence that no woman has ever benefited from it doesn't help our understanding of how our society works and how to change it.
Pure Marxist theory doesn't buy that there is a biological bent to the opression of women either. They theorise that it comes out of a primeval division of labour although the anthropological evidence is that hunter/gatherers were pretty egalitarian.
Like male violence, women's biology is a tool used to prop up the patriarchy but together they are not the whole story.
We can theorise about female biology being the reason for female opression till the cows come home, we can both offer a bit of evidence but neither have absolute proof. I think we need to consider how much the liberation of women gains from each stance. Do we present ourselves as having the body of a weak and feeble women but the heart and soul of a man or do we present ourselves as having the body of a weak and feeble women and the heart and soul of a feeble woman?