That’s a red herring. A person overlooking 5-15 kids is never going to be able to offer the care a one on one relationship with a mother can. Maybe a nanny might be an analogous alternative but the state will never be able to pay for that.
Some mothers have 5-15 kids!
Also that time has passed. All of Asia including south and south east are basically at replacement rate. Africa averages higher but not by a whole lot more and that number is dropping quickly.
There’s a reason women from wealthy families never work and dedicate all their time to raising kids.