What makes those male power figures focus on excluding women specifically from their roles? I doubt they care about the gender of their competition; they just want themselves to be the ones in power and nobody else, man or woman.
It's more that the people at the top have gotten there in the current situation. So emotionally they tend not to want to acknowledge what a huge advantage they and their peers have had getting there ... and they don't have any incentive to change things in a way that reduces that advantage.