I've never heard of such a policy, or perhaps I'm misunderstanding your comment. Are you suggesting that companies should have policies that affect what the spouses/partners of employees do in terms of caring for children? Why would an employer have any right to say what their employee's spouses/partners do with their time? Or are you suggesting that employers should somehow provide compensation in this situation? I also don't understand how that would work (and I don't think the lack of such policies is specific to software firms).
1: https://www.monster.com/career-advice/article/amazon-parenta...
I've never heard of it before now, and I worked for years as a corporate lawyer. And my lack of awareness isn't because I'm a man, as you've implied — my wife has also never heard of such a policy (and she works outside tech). Both of us have heavily researched the leave policies in our respective fields, as we have used them on multiple occasions.
If there are a bunch of non-tech companies offering this policy, then perhaps that could lead to your conclusion that it's one of the reasons women choose other fields. But based on what has been described so far, it's equally likely that this is an incredibly rare policy that does pull people into or push people from the tech sector. If there are sectors where this is common, please enlighten us!
Visualize it like large numbers of people are creating characters for an RPG.
For the female version of the character generator, "mother" is a class with a shitload of XP bonuses and it's the only way to complete the "bear a child" quest. Not all of them are going to do it, many will multi-class, but they have very strong non-economic incentives to do so.
https://www.theatlantic.com/science/archive/2018/02/the-more...
If we were to assume that biology is the reason why women avoid certain fields, then this logic should hold true irrespective of the amount of gender equality a region might have. In fact we should assume that the two factors should compound: That is, if a region heavily discourages women from entering into STEM careers then that combined with their biological inclination to avoid said careers means we should see the numbers crater.
So given that this hypothesis does not hold to be true we can clearly show that it's not biology that's the case. It's far more complex than that and is the result of various social and economical factors. Reducing the entire argument into 'it's biology' does a disservice to examining social trends and is mentally rather lazy in my opinion, considering it can be easily used to explain everything.