That sounds like a pretty bold statement but it's totally true.
and those are just the 'stand alone' rooms in NYC. There are dozens of additional comedy rooms in NYC. These are comedy shows that take place inside other venues like bars and restaurants. I'm not counting open mikes, there are dozens of them as well.
And those are all just in Manhattan. Once you leave Manhattan and got to the other boroughs and into the suburbs, you'll find dozens of more comedy rooms from clubs like The Looney Bin in Staten Island and Laughing Devil in Long Island City to Long Island's A-rooms such as Governors and The Brokerage. In NJ, Bananas Comedy Club and others line the Tri-State Area.
The best part about this abundance of comedy stages is that is give the young beginner comic an amazing amount of opportunity to get on stage and practice the craft. That's the most important thing a comic needs to develop their material, stage time. In other states where there may only be three or four places to perform standup comedy IN THE WHOLE STATE, this is a serious issue for new comedians who are looking to grow.
The result? Comedians from the New York City scene are the best in he country. Just be virtue of two elements:
1) Stage time – as I mentioned above, a hungry hustling young comedian can get up on stage in NYC every night, multiple times a night. These can be open mics, produced shows, club shows, storytelling show, alt show – there are almost endless opportunities.
2) Competition – There is no place that is more competitive for comedians than New York City. From competing in contests sponsored by the clubs to competing to see who's getting that 'Tonight Show' or 'Letterman' audition. It's that kind of competition that keeps you sharp. You just don't get that from a comic from the Mid West.