It's not just America. One reason is increased costs of living in big cities. If you buy a house, you probably are not going to buy one so large that you, your children, and your grandchildren (who will only be born a few decades later) could all live there comfortably. Instead, you just buy one large enough for you and your children. Or just you and your partner, if you are not planning to have kids soon.
But this means that when your children decide to have children, they will have to move away. If they are lucky, they can buy a house near you; but if there are many people who want to live in the city, and the new houses are not built often, or at least not near you, then they will have to move further away from you. And this is still just talking about living in a city... I haven't mentioned proximity to job opportunities or schools yet.
But this means that when your children decide to have children, they will have to move away. If they are lucky, they can buy a house near you; but if there are many people who want to live in the city, and the new houses are not built often, or at least not near you, then they will have to move further away from you. And this is still just talking about living in a city... I haven't mentioned proximity to job opportunities or schools yet.