It might take a long time, but at some point the chickens will come home to roost. Or roast...
Internal migration is a big thing even in countries with tanking birthrates. Entire villages are being emptied as old people die and their kids move to the cities for studies and work. The population overall is shrinking but housing demand in cities is still growing fast.
So yes, you can have a booming property market in a country with shrinking population. Nobody's gonna live in those forgotten villages with cheap empty housing but no schools, universities, hospitals, doctors, jobs and entertainment opportunities.
>at the end of the day has to pay for it to use it, otherwise it's just a ponzi scheme.
The housing market can stay irrational longer than you can stay solvent.
Safe to assume housing market aint going to go bust anytime soon if you live anywhere in the first world cities.
Have you seen the old city center of Prague in Czechia? or any old city center in any major city in Europe. These numbers only go up.