Mayor David Dinkins is the one who put thousands of additional cops on the streets of NYC and it was the Democrat President Bill Clinton who Put 100,000 more cops on the streets nationwide, Rudy took credit for it all. Btw crime didn't just drop in NYC it dropped like a stone nationwide, in fact the drop in crime starting in the mid 90's onward was a worldwide phenomenon.
People aren't leaving NYC because it's a failed city, some people are leaving because all the things that make NYC great are affected because of covid. Also the cost of housing in NYC is absolutely absurd and why is it absurd? In large part because a lot of people want to live in NYC rocket scientist! Also for a failed city NYC along with LA, Seattle, Chicago, San Francisco sure do have a shitload of people living there and are responsible for a shitload of America's GDP.