See section 4.3 Urban and rural prices move together. Urban prices may be unaffordable, but the data suggests they haven't inflated faster than rural. Perhaps urban/rural is too coarse a distinction to reflect the effects in major coastal cities, but the return to coastal cities didn't begin until the 1990s. Price inflation indeed accelerates in the 1990s in the U.S., but excepting Japan[1] it accelerates in all the other countries even faster; likewise for the 2000s.

[1] Presumably still reeling from its 1980s property crash.