I suspect the tradition that kids move out right after school is a result of countries (in my experience: US and Sweden) having had a lot of unused space, where

I suspect the tradition that kids move out right after school is a result of countries (in my experience: US and Sweden) having had a lot of unused space, whereas in countries which have always been densely populated, that expectation isn't there. compare https://ec.europa.eu/eurostat/statistics-explained/images/thumb/d/d0/Young_people_leaving_the_parental_household_2020.png/1200px-Young_people_leaving_the_parental_household_2020.png https://ec.europa.eu/eurostat/statistics-explained/images/th... EDIT: also, at the high end of the US real estate market, I note that the phrase "family compound" was often correlated with "price upon request".