So long as homeowners are considered some kind of protected class, where their investment is only ever allowed to increase in value and stability, this is going to happen.
But every policymaker is now a landlord, and there's a load of new homeowners who have essentially joined onto what should be a bubble, but because of the government backing (via policy) it's more of a pyramid scheme.
So they're terrified of anything that might cause the sale value of their house to actually get closer to the real value of their house.
And guess what, it's not sustainable.
So BlackRock is just buying everything it can, other private landlords the rest, and leaves those who want to buy a house to get stuffed.