That's exactly why we don't have many women in tech and most readers of HN are guys. All this political correctness and attacks on PG are simply BS: men and women are different. Not better, not worse, just different. It's evolution of sex, stupid. PS. My previous comment on this topic: https://news.ycombinator.com/item?id=7041221
But you haven't even tried to make a connection between the physical differences and the social differences. You just assume that all social differences are explained biologically.
The unknowns are how mental differences (expression of genes) are caused by environment or effect the environment.
This means we don't know whether a 50/50 split in some field is natural or a result of society railroading people into the field. It seems to me that the best way to handle policy is not to base it on unknowns, so that's why I favor policy that ensures opportunity to work in specific fields but doesn't try to balance them.