I've pondered on this a lot. Houses have been treated as "nest-eggs", which is really a fancy term for a fallback plan, for quite some time. The housing market really only got out of control after the 80's which coincides with when mortgage packages started getting sold on the stock market. To me, that, city zoning, corporate SFH buying, and state governments that have economic policies that embrace/grow inflation seem to be the actual problem.
I still think it's worth while to have house equity as a way to securely store money, but the government has to protect the housing market conservatively to make that work. Just like anything else the market is a system of incentives.