Nah, number of properties is a pretty fucking good metric.

Being a "bad" landlord isn't the issue, the issue is taking properties off the housing market for rent collection, and driving up prices for everyone else in the process.

There are more empty units in this country than unhoused people to fill them, this housing crisis is one built entirely out of artificial scarcity created by letting speculators buy up supply basically for the purpose of scalping them to poor people who can't say no to the product.

It's the same kind of "market efficiency" that has ballooned medical costs, who can afford to compare costs on a kidney transplant? Nobody. Who can afford to shop around and wait on houses? Unless you're very lucky in today's economy, also nobody.

Housing does not abide the same market rules as designer T-shirts. Necessity goods will inherently have a hostage effect on the customers where you could in theory charge any price and just make the disinfortuned eat shit for it.