For high volume routes rail is best. For lower volume automated cars on the highway are more efficient than flying by enough that only the rich will fly - just like today. You can book a helicopter flight home today if you are willing to pay for all the fuel. However even at 1/10th the energy cost, a car will be vastly cheaper and so what most people will choose. We also will continue to use trucks to move freight for many of these trips, so the roads will exist either way.

There is one other issue with flying: it often isn't legal - for good reason - to fly and land where you want to be. For a 300km trip flying to an airport is fine (if there is one close - they are not evenly scattered around), but at 50km you may as well drive the whole way instead of transfer at the airport - unless you live very close to the airport (which you won't because of noise)