Quite often taking a car took longer for me, including finding my Uber or Lyft in a sea of others (great system, really, requiring everybody to find "theirs" when they're all pretty much doing the same thing!), navigating cancellations etc.
Of course, if you live far from public transit it's a different matter, but many people in NY do live close to a subway station.
The only time I was late to JFK was the one time I tried to get there by car and ended up on a ramp in Queens, completely stationary, for over 2 hours.
