It's New York, they can charge basically whatever they want and somebody will still rent it. If they can't afford the rent, they'll turn it into an Air BnB.
This... really isn't true. Very expensive markets are still markets - you are, for example, very unlikely to find a taker for a studio 5th-floor walkup on the Lower East Side for $5k.
NYC rents are pretty nutty, but it is still a market, and pricing pressure is still very aggressive in this market. The volume that exists in the market, and the similarities and substitutability of apartments (one walkup is largely like another) all serve to apply more pricing pressure.
