It’s nothing about agreement. Everywhere has declining birth rates once they hit a modern standard of living for at least a couple of generations. Not because

It’s nothing about agreement. Everywhere has declining birth rates once they hit a modern standard of living for at least a couple of generations. Not because people think fewer children are a good idea, but because having many children in modern world is unpleasant and very few want more than two. I think it mostly has to do with increasing desires for a high standard of living when it becomes possible and the pressure of high density cities making lots of kids an unattractive prospect.