I think that is also a subsequent symptom. Twenty-something newlyweds are less likely to afford the down, so the demand feels to the markets artificially low. This causes a new-build supply correction. No one makes modestly sized housing because the money is in mid-sized single family homes, multi-plexes, or apartments. Maximize the size of home you can fun on a lot, and your lot ROI is better as a housing developer. Too small and you'd be better to double up on a lot and make a duplex or quadplex.

If you want a modest house, you'd be best off with a trailer and a little land in the country. Plus, with remote work being what it is nowadays, that's really a great option.