It's the most international city in the US, and a disproportionate number of people who use the roads (taxis, delivery drivers, etc) grew up in places that have a traffic system very different that the US's. People in New York routinely run red lights, roll through crosswalks, ride in the shoulder - things that you might encounter in other countries, but are generally considered disrespectful/dangerous in the US. When so many drivers grew up driving in places that tolerate those behaviors (either in their home countries or as native New Yorkers), it creates a road culture that's very different than you'd expect in other parts of America.
In other cities, you can take a "trust but verify" approach to traffic. Drivers will respect traffic lights. Pedestrians will cross where they're meant to. People will (only) use the lanes painted on the road. You have to be alert in case an outlier does something differently, but we generally consider those people selfish exceptions.
The written rules and the practiced culture deviate immensely in New York. You can't just operate by the rules and expect that everyone else will too.
