I respectfully disagree. A Formula One car cannot complete your street challenge either, but I think nearly all people would agree it's most certainly a car.

However, I can think of one criterion that you could use to disqualify vehicles like this as "cars" - the fact that it gets its thrust directly from a reactive jet engine, rather than by turning the wheels themselves. (They're basically zero-lift jets with landing gear that never goes up. )

 

Agree with Mark on this one. The wheels aren't driven, which makes it a non-flying aircraft. If they get the design wrong, it may be a short-flight duration aircraft.

 

If I strapped a jet to my S2000 and drove it around town like that, I don't think people would spit in my face because it's not "really" a car.