> I've seen it argued that, paradoxically, the richer and more egalitarian a society is, the more the differences are magnified in the kinds choices individuals of both genders make.

There's absolutely nothing paradoxical about this. The more wealthy a society is, the less incentive there is for women to work instead of being the primary full-time caretaker. Women are happier in single-earner households where they don't have to work or can work part-time at their leisure. This usually means they chose the right partner, e.g. a high status male that lets them survive on 1 income (presumably high).

Beware the cognitive dissonance that liberals are so intent on perpetuating that empowering women has anything to do with the workplace. It doesn't.