This isn't an actual argument against severely limiting cars. Most of the people traveling the super-region already use the subway or buses. That will become easier and more efficient without private cars.
That only works well if your origin or destination is in Manhattan. To go from Union City NJ to Belmont Park on a weekend is a 45 minute drive or > 90 minutes on transit consisting of bus, subway, LIRR, another bus.
There are similar examples even within NYC, like Red Hook to Jackson Heights.