I think the societal biases are imprinted in people during their social development.
Girls are less likely to be given the equipment and backing to get into software development at an early age, and their peers would rarely understand such an interest.
The field and the associated character traits around it are viewed as nerdy or boring, the people who don't give a stuff about such judgements seem to be the people who do gain an interest in the field and consider working in it.
The gender imbalance in fields like programming and nursing is larger in the most "fair and evolved" societies (e.g. Denmark), because these societies allow biological gender differences to more freely assert themselves.
Affirmative action reeks of plastering over a bug instead of squashing it at the root cause.
I think companies can take steps to improve outreach to excluded groups, and set up policies to help reduce exclusionary behaviour in the workplace. I don't really care if it's their fault or not.
It usually reflects the pool of applicants.
If women are self-excluding, what is causing the hostility in that environment? If they're systemically-excluded, how do we remove it?
I had to seek out recruiting female engineers. Now with more balanced gender ratio in the company, things are just better.
The implication here is that earned (through training) software and programming skills are equally distributed among the entire population. This is simply not true just by looking at StackOverflow/CS major demographics.
They are finding the best female developers. There just aren't that many (for whatever reason)
This sounds like you think companies don't have an obligation to improve their environments so that women feel included. Consider a developer that you would say is among the best: would she accept a position at your company? Why not?
I agree, that's why I think companies should consider what is putting off women & why the gender balance in tech is so heavily weighted towards males.
That is, most companies (regardless of conscious choice) are finding the best (young, white) male developers only.