paygap paygap paygap

I keep hearing that there is no pay gap. That the "pay gap" exists because studies don't take into account women leaving work after having babies, or that a large amount of women work in part time low paying jobs. (Out of pure choice no less.)

So to that I just want to say bullshit is all. To quote the article:
"So let's just get this straight right now, says Murphy: That 23-cent differential is not because some women take time off to give birth or raise children. The pay-gap figure measures only women and men who work full time, for a full year. It does not include women who took time off during the year or worked part time."

I hear that women have low pay because they're typically not aggressive negotiators, so they end up short changing themselves by on average negotiating for lower starting wages then men generally do. (Where how much they get payed for the next job gets based on how much they were paid for the last job etc.)
I'm down with that. it makes sense. Hearing someone make this argument, and also make the argument that the wage gap doesn't exist. Well... it's startling is all. If women generally have lower pay because they're not good negotiators, then... I mean the start of that sentence was "women generally have lower pay" right?
The thing that gets me about that is that if women are less likely to be aggressive in negotiating, isn't that a reflection of the fact that women are trained in society to be passive while men are trained to be active and aggressive? I mean, that seems like a symptom of the way women in society are trained to be feminine. In short, it seems rather patriarchal.

The people who point out the pay gap doesn't exist due to patriarchy, it exists due to womens own lack of being aggressive are often the same people who will say that domestic violence doesn't affect women more then men, and that women are equally aggressive.
Either women are less aggressive (due to sexist societal training, in my opinion) and that accounts for the pay gap - or men and women in this society are equally aggressive. It doesn't seem to me like it can go both ways.

*Remembering that I define patriarchy as systems that benefit men at the expense of women, and not women being deliberately exploited by men, all men. Patriarchy is a society thing that benefits men. Saying "women perpetuate it" doesn't stop it from being patriarchal.