If it was simply a population problem, then why do long-time residents tell me that it wasn't always this way?
Specific reforms intentionally undertaken to solve known problems with the system, made the system work better.
As a life-long New York resident until about 4 years ago, I can also tell you that I probably wouldn't disagree if you told me you thought this was "not possible in New York."
(And intuitively I'd say, it's not because of population numbers, but I can't put my finger on exactly what it is. There is a different mindset, whatever causes it I can't say, but I noticed immediately when I moved here, I still tell folks this place really just isn't like New York.)
To elaborate a bit more, I felt like part of the New York mindset was basically psychologically planning oneself around not getting robbed. There were plenty of ways to get robbed that people just don't worry about around here (and some of this can surely be attributed to population issues.) I'm not just talking about general common-sense things like making sure that valuables are not left visible in your unlocked, parked car. I mean up to and everything including neighborhoods which don't have enough driveway space for everyone in large duplex houses to park their cars, where the streets are marked for opposite-side alternate day parking.
So I don't have a private place to park my car at my rented house, and I have to park on the street, but I can't park my car on the street and leave it for 48 hours time without getting a ticket. This makes sense in Upstate New York as a condition required for Winter road maintenance, so that plows can get in and clear the snow off of the road. Only it's not just a condition required at Winter time, and when you point this out, people just accept it and say something like "yeah, well, they gotta make their money somehow..."