[geofft]

I think he's claiming his competitors are overpaying men by artificially pretending supply is half the size it actually is. Or looked at another way, the market value of men is determined by companies that hire everyone + companies that only hire men, but the market value of women is determined only by companies that hire everyone, so demand is lower. Either way, it's not "underpaying" relative to either intrinsic value or value in a fair (everyone is willing to hire everyone) market, which is most of the moral argument for why underpaying is bad. It's "underpaying" in the strict technical sense of paying less than what others are willing to pay men, but that only applies in the hypothetical where one single woman were being hired as if she were a man; if all women on the market were hired like men, supply would increase which would affect everyone's pay.

I think there are multiple solutions to a gender wage gap resulting from markets with irrational participants, and reducing the market value of the overpaid gender is a perfectly valid way to accomplish it. I think that's what he's doing.