As marcush points out upstream, I belive it has a lot to do with traditions and interests, not enough women has been involved in racing
to make a statistical impact in the results, simple as that. On top of that, those who made it into F1 perhaps didn't make it on merits anyway, female equals of Andrea de Cesaris perhaps, just having a well connected dad.
Not denying the physical and psychological differences between the sexes, I think a larger percentage of professional females involved in F1,
would be a healthy counterweight to the Briatores and pitbabes alike.
And no, this was not written with my mistresses gun to my head.