> people won't rent places out if they aren't covering their mortgage

btw this is usually false, and mostly irrational.

1. Realize that every landlord has a different capitalization structure. Many likely bought decades ago and thus only owe a fraction of what the current market selling price is. Additionally we also have had a long period of ultra low interest rates so their interest rate is different than what new entrants are paying. Because their capital cost is lower they can actually offer for far less than the (Interest+Taxes+Insurance+Maintenance) costs that a home owner would have to bear.

2. The rational move of a landlord is to price competitively based on what the market can bear, even possibly losing a little money per month in cashflow (but less bad than the appreciation rate and cost of disposal/selling/defaulting).