The thing is - positive discrimination doesn't solve the problem, because it comes from school. You need to encourage girls to take science classes - it has to be expected of them that they do so (rather than go towards, e.g., humanities). That, I don't think is actively happening in the US or even some parts of western europe.... by the time you're dealing with graduates, it's already too late to fix the gender-imbalance problem.
[1] My little daughter's godfathers are German (she grew up in Romania, but he didn't). She told me that among german women, it's a thing of pride to be bad at math. And that her daughter was praised in school that "you're pretty good, for a girl". With that sort of attitudes during childhood... it's bound to be hard to get gender balance later (that "praise" would be perceived as insult here)
When I was going to school girls were usually better at math. I remember getting help from them with some calculus problems.
My CS teacher in high school was a woman as well and before teaching she worked as a programmer. She was a great role model for girls I'd imagine. Well she was a great role model for me too because she was a great teacher.
Not being familiar enough with history of this in US/Silicon Valley, want to ask: were things always "unequal", or did things go wrong somewhere along the way?
So yes, it makes sense to have a movement for diversity here, because something is pushing women out of these fields, so we have to push back.
I'm not sure for the increased participation of women in tech though. Maybe better education? Maybe less of a "computer lovers are all nerds" culture? I honestly don't know.