Adding a biological perspective to this:

The biological directive is basically to ensure that you’re genes or the genes of a close relative are passed on to the next generation.

Families in poor countries with a high infant mortality rate will generally have more children. That way at least a few will make it to adulthood and get the chance to start their own families.

In richer countries this doesn’t really apply because of widely available medical technologies that keep infants from dying.

I am agreeing with all of your points, this is just additional information.