"Landlords" (aka individual non corporate property owners of more than one residential dwelling) and real estate companies (those with portfolio's of land assets rather than those that just take a commission on sale) can do pretty much the same thing if the numbers pan that way and/or they have no stomach for dealing with Tennants for marginal extra profit.
Ownership of rentable property that is empty is a thing across the board, at least here in Australia where (stupidly(?)) investment rules and returns have made multiple property ownership a sound investment that grows regardless of occupancy.
Don't even need a long ( > 10 year ) time horizon, flipping on a two or five year scale still makes money regardless of renters being present or not.
It seems like you're saying, that PE, landlords, &c, are in a market where a landowner can hold on to property, not rent it out or put it to other productive use, and still make money. That is a problem, but not a problem with wealth or wealthy people per se.
Ownership of rentable property that is empty is a thing across the board, at least here in Australia where (stupidly(?)) investment rules and returns have made multiple property ownership a sound investment that grows regardless of occupancy.
Don't even need a long ( > 10 year ) time horizon, flipping on a two or five year scale still makes money regardless of renters being present or not.