The point you’re missing is many of those home were bought as investments. No property tax makes them good stores of wealth, no carrying costs and my god a less risky investment than Chinese company equities.
Problem is that despite the urbanization potential that doesn’t mean the properties are correctly priced or that they’ll continue to go up.
I spent some time in another Asian country that has a per capita GDP 1/10th of the US, yet housing prices are comparable to the mid-west US and most are empty. Most are owned by the ultra rich and used to launder money. And I’m not talking prime location, these are basic apartments on the edge of the city going for $100,000USD or 30-40x average annual salaries. Unless GDP goes 3x no way those prices will hold.
It’s a massive bet on continued income growth and demand for real estate which is not a given, which Japan showed with its massive property bubble.