Women are nurturant, men are instrumental. The culture argument suggests that we learn sex appropriate behaviors from those around us - conventional wisdom. Thus women are weak because of thousands of years of evolution in which they did not consistently perform physical tasks. Women are verbal and scheming because men have afforded themselves the social, political, and economic resources. Women have to align themselves with a powerful man to achieve in those arenas.
Women are nurturant because the have been delegated nurturing responsibilities.
Effective contraceptives reduce the social significance of this one. Different cultures have different value placed on gender. Males most often inherit power, and keep it. Sometimes this is not the case. Idealization of them is dysfunctional to change.