Just off the top of my head:
-"House Flipping" culture
-Short-term rentals and AirBnb
-"Professional Landlordism"
-Corporate residential landholding
-Rabid boomer landowners who lose their minds when any rise in property tax gets mentioned, which results in artificially inflated property valuations
-No rent control
Obviously the REAL answer is Capitalism, but the above phenomena create ripple effects across the whole housing market, which is something that the r*dditors always overlook when they quote stats that say "corporate ownership of residential properties only represent a small fraction of the market." Yeah, maybe they do, but even that small fraction ripples out to housing precarity for millions of people.
I'm here and lurking - my heart is out for you