They also have this law now:

https://www.coleschotz.com/copa-changes-the-game-for-nyc-multifamily-transactions/

If you sell a multifamily building, the government has the right to match any offer. Further, there's a waiting period before you can sell. That will make buyers reluctant, if they have to wait 90+ days for a deal to close and they risk the government matching their offer and taking it away.