The 1/2 surviving child/per person is derived from rational thought and evaluation of our planet’s existing resources. Children are expensive and everyone pays for all the children in one way or another. It’s not always about the money.
When we have a planet that doesn’t expand and most of our resources are not renewable, it’s a zero sum game. Someone in the gene pool who spends all their life making a dozen babies benefits proportionally more than someone who has 1-2 children.
Also..this need to keep having babies is a scam perpetuated by organized religions of all types because the state was always funded by religion. And more subscribers means more power. That’s the kind of bullshit that needs to be stopped in its tracks. Have a nice day!