The real tragedy in the discussion is this assumption, quoted from the OP: "His hypothesis implies that personality differences mean a smaller percentage of women will be interested in and/or qualified for a Google job than men" Empathy and social intelligence are actively disqualifying factors for a job at Google, or software in general? That is so wrong on so many levels. I really like Bob Wyman's take on this: htt…
But consider that in order to get a job as a programmer, I first had to spend 4 years taking relatively intensive courses in math and computer science (even longer if you go back to elective courses in high school), and empathy was not an important factor in getting through my coursework or examinations. Sure there are other paths into the industry, but no matter how you get here, the fact is that learning to code is intensive.
Consider also that a large portion of the population can't pass a FizzBuzz programming interview (at least if Jeff Atwood is to be believed). And if you can't write FizzBuzz, no amount of empathy in the world is going to make you a good programmer.
So yes, "soft skills" are tremendously important. But "hard skills" take priority. And whatever the cause may be, the fact is that right now there is a larger proportion of men than women who possess those hard skills.