Think I've heard anecdotes about Tokyo being pretty affordable as well. Quick search shows less than 1/3 of income typically spent on housing, which is much better than major US cities.
Also building a house or apt building that can stand for 100 years is very different from one that stands forever, for example steel beams can be used as foundation instead of having to pour concrete
Occasionally if you get unusual spikes in building materials and labour costs then the house itself can appreciate in value because it costs more to replace it, but that's rare enough.
Intuitively, it would make sense for housing prices to decrease when the demand decreases, supply being equal (It's not like housing deteriorates significantly in the short term).
that also leads to a lot of experimentation in architecture, since this building ain't gonna last so get weird. downside is it leads to a prefab corner cutting approach.
my brother lived in japan for a while and he loved it, both the long-standing rural places that were legit old school, but also when he was in the city and sublet some hypermodern, querky places on the cheap.
There is a history of substantially updating building regulations every time a new record is set for largest earthquake in the modern era; and so if you are buying historical, you are buying a less safe property that could kill you.
The last major earthquake updates to the code were in 2000, so there isn’t a lot of historical housing stock without this confounding factor.