(2) It's known that generally, as a nation becomes more wealthy (and socially/technologically advanced), fertility tends to drop. Well-off populations have few

(2) It's known that generally, as a nation becomes more wealthy (and socially/technologically advanced), fertility tends to drop. Well-off populations have fewer kids. As you wrote: the vast majority of countries have already passed this point, or are heading there. That implies there's fewer kids to care for. And thus fewer stay-at-home parents needed. Even if classical gender roles stay the same. What will those now-not-parenting people do? All else the same, logical expectation: a large % of them adding themselves to the job market. Ok there's also smaller families. But juggling 1 kid & (parttime?) job is still easier than doing same with say 3..5 kids. In short: countries moving up the wealth/development ladder will logically cause traditional gender roles to shift. Probably no coincidence that it's usually less-developed countries where women are forced into traditional roles.