I generally agree with this, but it's worth noting the places that do have public housing have notably lower homeless rates when compared against drug use rates. Furthermore, most housing assistance is done through section 8 vouchers, which you would presumably control for if you repeated this experiment in the US.

Many of these private landlords are non-profit orgs.

The state of Massachusetts has subsidized housing for the elderly. And they are closely monitored by social workers.

My uncle lives in one of these apartments, and whenever he goes out of town, he has to notify the social services office. Otherwise, they will open the apartment to see if everything is okay with him.

If he's gone for more than three months, he loses the right to use the apartment.

Edit: minor corrections.

It references "Gov.uk. Trends in tenure. 2022"