Housing costs are up, but we are also consuming more housing (sq foot per capita).
Believe It or Not, Real Estate Affordability Hasn’t Changed Much in 40 Years: https://www.supermoney.com/inflation-adjusted-home-prices/
Believe It or Not, Real Estate Affordability Hasn’t Changed Much in 40 Years: https://www.supermoney.com/inflation-adjusted-home-prices/
The factor of square footage can be explained by cheaper materials.
Anecdotally in Boston there has been a longstanding push towards "family housing" this results in a relative oversupply of 5+ bedroom units that are almost exclusively leased to large groups.