So we saw marked increases in the ratios of housing prices and debt to household incomes up until the early 2000s. At the time, there was much discussion as to whether these higher ratios were sustainable. As things turned out, the higher ratios have been sustained for quite a while.
This largely reflects the choices we have made as a society regarding where and how we live (and how much at least some of us are prepared to spend to do so), urban planning and 3 / 14  BIS central bankers' speeches  transport, and the nature of our financial system.