Economically speaking, I suspect this is more to do with the superior position of women, as a class, in setting the standards of what an acceptable relationship looks like.
If husbands are willing to do heavy lifting, wives would be economically irrational to do their own heavy lifting. I'm pretty suspicious that the deal offered to a housewife comes with better quality of life outcomes than the deal offered to most engineers. I've always assumed it is linked to the relative excess of young men to the number of young women (something like 107:100 or close to [1]).
It makes sense to me that the group with most power in establishing a relationship would choose not to be an engineer if they could be, say, mind the house.
Maybe deep down humans feel that they're at evolutionary dead end and decide to off themselves as a society? I could easily see why today's western society (and possibly others as well) may be far from optimal. Yet I'd prefer to try to fix it.
What is funniest, people advocating for "progress" etc frequently are those who have no children. Although old good "you're not grown up till you got kids" outlook is looked down nowadays, I can see why it'd make sense. If you don't have kids - you don't have skin in the long game. Nor experience what it's like to play in that mode. I wonder how the world would change if we'd only allow people with kids to vote and/or participate in politics.
As why many girls make that "decision" at around 12 - they might be smarter and see that they don't have to work that much anymore. Maybe in the past when things like cooking for 10 people family or washing clothes/cleaning were super difficult the partners had to form a team; these days most of this is semi-automated and allows different strategies.
Do you really believe that girls aren't making conscious choice to stay away from "weird smelly" engineers in STEM fields that are now popular wrt. $/status but were completely undesirable 20 years ago? Have you grown up completely isolated from young females and couldn't observe what were their choices? Yes, I have seen a lot of men dissing them "just females, can't be good" (I hated it in my idealistic youth), but then later you observe their choices and they aren't doing themselves any favors either, usually picking "safe choices" instead of risky ones needed for success.
I'm a female founder who majored in CS and left my PM job at Google to start a company, so I have "observed the choices" of many young females considering engineering. It's not enough to say that "women are just choosing the wrong thing" - we need to find the underlying cause of those choices if we want to shift the demographics.
- I can't take Sheryl seriously; she's not a prototype of a woman that risks a lot to achieve success and her dating advices IMO just poison the well to most regular women, as not many men contemplating serious relationship want to have anything with women following her advices
- from my personal experience of running multiple companies, I once offered significant equity in an e-commerce startup to a woman as one of two founders. Her reaction was that once the company nets $1M, I can give her 50% stake. This risk aversion is the norm. I have only one counter-example of a female CFO that was driven to succeed against all odds.
- young males are now seriously disadvantaged; they have to be like 50% better than females to even get to interview stage in most lucrative tech companies. This is obviously not sustainable nor fair and a backlash is mounting. Either they completely drop out of society, or become associated with extremist male-only movements. This is very troubling and a waste of potential.