"advanced economies" don't change your grandma's diaper when she shits herself, a human does. "advanced economies" also don't build airplanes with wings that don't fall off or maintain nuclear powerplants.   imagine your water system when all of the engineers have retired because they're 70 years old and there aren't enough young people to replace them. everything you use in life was made by someone and is maintained by someone. demographic decline is a big deal because of which "someones" are going to be left.
United States