> By raw statistics, white men still wield most power in American society (and thus the world), and so the progressive culture that is dominant in media is the culture being written and put into vogue by people who are white men if you merely draw on the statistics. 

Those would primarily be "progressive" white men though, which still gets to the in-group/out-group dynamic where they will more closely associate with a racial or sexual minority then they would to a conservative white male (a value match vs a skin color match). So the effect is the same, is it not?