If anyone wants to see what New York City used to look like in the dark ages, watch Taxi Driver. As that was actually filmed in New York in 1975 and they show you all the seedy aspects of the city.

NYC is in decline because there's no real incentive to live there anymore. You can't enjoy all the culture that New York has to offer because of COVID. White collar workers can work from home. Housing and rent is expensive in New York. Crime is up. Taxes are high in New York, especially NYC which has it's own city income tax. The wealthy are the most mobile people so no shit they are going to leave. The poor who can't afford a UHAUL (moving is expensive) or who don't want to break their 1-2 year lease are stuck there.