The thing that particularly strikes me is that as far as I understand, any specialized group will have disproportionate representation of non specialized groups

The thing that particularly strikes me is that as far as I understand, any specialized group will have disproportionate representation of non specialized groups from the general population. Sufficiently small samples from a larger group will not represent the larger group unless the samples are deliberately chosen for a given property. However, let's be honest: your company is not hiring the absolute, top 0.1% best programmers and totally doesn't need to (and you don't know how to find that SS tier programmer anyway), so deliberately biasing a small group towards gender/race/whatever balanced representation isn't going to hurt your competitiveness. But if the goal is to solve misogyny or other problems within a particular microculture, it's not clear to me that proportional representation will actually change that microculture instead of just ending up with weird shit like #leanin.