Sure, eventually you get an equilibrium. Because nobody else wants to be a landlord you can charge so much that it's worth the aggravation. I wonder how many of these new units would be needed if people were more willing to rent out unoccupied units.
The problem isn't as acute for big companies. If you have 1000 renters you have a staff to deal with problem tenants. You have lawyers on retainer. You expect some number of tenants won't be paying rent at a given time, so you charge everyone else enough that you still make money.
The people who get screwed are the duplex and fourplex owners who wanted to use rental income to supplement their retirement.
Which, of course, is part of the problem.