Why do we as a culture reward female outliers?

I see it all the time now, from an early age females are encouraged to do "boy stuff" (interests and activities, get into science, have a career instead of building a family, get into masculine sports (e.g. serious lifting), etc. While I believe that with serious work they probably can get close to the male level in these pursuits, more men that try some traditionally male thing are going to succeed than females that try the same thing.

Wouldn't it be more logical then not to reward female outliers and to encourage girls to make feminine life choices, just from the standpoint of efficiency?