To put it simply and bluntly - those cultures remembered it takes a village to raise a child and have sane cultural expectations around children and child rearing.

In the US the typical "middle class" child raising experience is utterly miserable. There is very little expectation in the rest of the world to end your life as you know it just because you had kids.

Family, friends, even the community all sort of collectively engage in child rearing. In the US it's gone down this relentless road of sequestering oneself off from society whilst simultaneously being expected to devote your entire existence to child rearing or be seen as a bad person.

This is a topic I've thought a lot on and have my ideas of what caused it, but it's really not for a place like HN :)