There are so many transit improvements that should and could happen in the NYC metro area that never will... Simply because NY and NJ are two separate states that can't agree on what should be done and who should pay for it.

Now imagine each of the five boroughs having their own transit authority with rampant nimbyism trying to kneecap them and you get the Bay Area.

Even unifying the SF metro into one city won’t stop the nimbyism. Look at the state of public transit within SF itself

Look at the TZ bridge as an example. Closest you can get to NYC to build a bridge without dealing with the port authority.

The benefits aren't limited to the ground - if we had dramatically upgraded the speed with which Newark airport could be reached from the city, LaGuardia could have been deleted and the airspace could be decongested as well. As it stands we seem to be stuck with the airport triumvirate forever.