Eventually, it might be. Currently, the US airspace system could handle ~10x the GA traffic we have today (I'm basing this on the fact that when we were building it up in the 70s, we were selling and flying ~10x more airplanes than we do today).

However, as we get to much larger scales, we can start using our aircraft to actually augment ATC to help handle the traffic. the airplanes can have more intelligent communication systems to coordinate with each other and the pilots and automatically send and receive data to/from ATC with digital comms rather than voice radio. That's an entirely separate project and company though when Airhart is a huge success and we hit this problem :)