People are making way too big a deal of genetic predisposition. Yes, there are genetic predispositions, like how musical talent may run through some families, but what matters way more is how we are brought up, and how we choose to act. If someone is a musical virtuoso, they became that way not because of the talent they were born with, but because of the encouragement of their parents and environment and long hours of practice they chose to put in.
Young minds are impressionable, and if you tell a young person they're probably less capable of something, they probably will be. Even as the stereotypical nerdy white male programmer I can see how people look differently at a young girl who is interested in computers. It is considered odd, if not improper. Boys never have to contend with this bias (although they have similar yet opposite biases in different fields, like child care). Inevitably this societal pressure will cause fewer girls to go into programming, and in turn fewer women to end up at google. That's not a consequence of some genetic predisposition, it is a consequence of being brought up in a world where not everyone is treated equally.
How do you flip that around? You stop thinking in terms of averages and you start thinking in terms of individual opportunity. We treat every child as deserving of the same chances as any other child, and we stop trying to steer them into directions based on their birth. That requires a modal shift in thinking where gender is just not a factor anymore, for any profession or any talent.
The diversity memo's failing is not the statistics it cites, it is that it furthers the notion that diversity is a set of statistics to control for. True diversity is about ignoring statistics and instead giving every single person the same chances, regardless of where they came from. I want my daughter to have the same chance of becoming a programmer as my son, and my son to have the same chance of becoming a kindergarten teacher as my daughter, and for no one to tell them either choice is odd or improper.