> It is actually pretty deranged that we have each parent raise their own kids in relative isolation (until school).

The quality of communal childcare varies widely; and having seen some examples of under-stimulating and inattentive care settings, I’d say the choice to raise one’s own children can be more rational than deranged, particularly if you have a caring and empathic relationship with your own children. In my own n=1 experiment, the decision to leave behind an income in the mid six figures to stay home with my child during her early formative years was anything but deranged.