India has declining birth rate as well and probably below reproduction rate already. People are not stupid. It just takes them some time to adjust. African soc

India has declining birth rate as well and probably below reproduction rate already. People are not stupid. It just takes them some time to adjust. African societies may still be forced to use children as free field labor. The more centralized their agriculture becomes, the fewer children they would need. The most important resource to spend on children is time. Even if you decide to cut on spendings, it does not add any extra time. With both parents employed full time, there's very small wedge to stick children into.