Some of those properties are profitable to rent out. Some are not. You rent out the profitable ones. You don't rent out the ones that are not profitable, you just wait until they're worth significantly more than what you paid for them. When they are, you sell them, and you buy more property. Each property leverages the subsequent properties, in terms of both the mortgage credit you have access to, and actual money gained accumulated from rent and sales.
And people who do this are always people with perfectly good couches in their living rooms but would never let a homeless person sleep there, but want others to give up a entire building.
tl;dr: 2 years free rent with the condition that the tenant doesn't ask for a lower price. due to language in the contract the rent can not go beyond a specific (low) value. the loan isn't held by the bank but immediately restructured and sold as a CMBS (https://en.wikipedia.org/wiki/Commercial_mortgage-backed_sec...)
here is the reddit post that he recaps: https://www.reddit.com/r/nyc/comments/innhah/nearly_twothird...
Let me explain it to you simply: The landlords made a bad investment, bailing them out forces everyone else to pay for it. In the "it's my property" sense it's identical to forcing someone to house homeless people (although the comparison still isn't the same because the landlords generally don't live in the buildings they're renting out.)
Simultaneously buildings would be converting into condos because they were unable to fill vacant commercial space. As an example, two buildings where I worked had this happen: 70 Pine Street (AIG) and 75 Wall Street(JPMorgan.)
Doesnt the market meet somewhere in the middle?
Every city in the US has a similar issue including the one near where I grew up and it's the weirdest most broken thing. I remember many times walking down streets flanked by empty buildings with homeless people sleeping outside.