What's the difference between the two? Every rental unit is ultimately owned by someone. And if rents are falling but your equity is rising, you are still coming out ahead.
A lot of large apartment buildings are single-owner/single-management with all units rented. Usually some sort of corporate owner.
Condo buildings might have id rentals offered by individual owners.
The former is (possibly) more likely to ask questions like “is it better to sell the whole building in the face of falling revenue?”
The latter, if their mortgage is lower than rental income, might just hold the unit regardless of the unit’s value. Probably a much less sophisticated owner/landlord than a big corporation.
It's one of the hidden problems of the housing shortage: condos are very difficult to get financing for which artificially deflates the market for them. Which means that our best form of housing in terms of the efficiency of building units isn't terribly attractive to actually build.
I wasn't aware of this difference until just now.