The Giants and Jets get knocked mostly for factors out of their control. The New Jersey stadium creates a small disconnect with the team and it's not a great home crowd for either squad. The Giants are a bigger deal, but neither team can unite New York City. It's more of a baseball town. If the Knicks were good, it might be more of a basketball town. The team doesn't mean quite as much to the community it calls home. Sorry.
My favorite piece here of this "superb" article:
No team has a stronger connection to its fans than the Packers. They are smarter and more loyal. They demand better coverage. It's a lifestyle.
I didn't realize that they had tests out there to measure the intelligence of the different fan bases.