The last reference indeed argues in favor of too much financialization of housing units but that blog is also tripping a lot of my crackpot alarms.
Can you succinctly explain why you believe the low vacancy rates in major metros (which I think we agree is the cause of high rents / purchase costs) are caused primarily by units which are intentionally held empty despite demand?
In partial defense of your assertion, the FRED data does show that 1/4 to 1/3 of vacant units are for sale or rent at any given time.
https://fred.stlouisfed.org/graph/?g=1oeIe
Total vacancy rate seems to hover around 10%? Rentable and buyable unit rates are an order of magnitude lower.
I’m not convinced that the Fed owning a bunch of mortgages is evidence that private companies bought homes and aren’t renting them. Wasn’t that a bail out to prevent people from losing their homes (because the companies owning the homes weren’t solvent and I guess if the company fails maybe you get foreclosed? I’m not sure why we did things the way we did in 08)
Could not the explanation also be that a lot of homes are in places that lack demand and therefore the owners don’t bother putting them up for sale or rent?