I think the idea is that if the market demand is such that it allows them to raise rents, they'd already have done it, whether or not expenses justify it.
If they can't raise rents to cover expenses plus "enough profit to make this PITA worth it" then things (slowly over time) grind to a halt.
Did tariffs raise prices? Or did prices stay the same because "if the market demand is such that it allows them to raise [prices], they'd already have done it"?