The volume held by investment firms and the like is large in a sheer numbers sense, but virtually nothing in terms of its percentage of the whole sum of residential real estate.
The fact is that we have been lagging in the supply side for decades and the Great Recession and then the COVID Pandemic cut new builds even more drastically. There simply isn’t supply available to address the demand at a reasonable and accessible price.
Okay, but your assertion was that there are not enough homes currently to support our population if they weren't traded as a commodity. In NYC alone there are over 3.6 Million Housing Units and a population of 8,258,035, with about half of the units being rental and about 1/20 being vacant.
You haven't provided any evidence that there aren't enough housing units in the USA.
A decline in housing project expansion is meaningless without context of how many are actually in use.
Urban centers should have drastically more rental units than urban, exurban, and rural tracts. An unoccupied rate of 5% is pretty good to cover units in transition.
So if an average of 2-3 people are in a home there are enough. Since our current system puts home ownership just out of reach, selling former rental properties and properties owned by overseas investors would probably be the bump we need.
I'm worried that large developments could be harmful to the environment and a waste of resources.