The problem, as I see it, is, whilst we've trained the "great unwashed" to be able to drive a car with just about acceptable degree of competence, flying an aircraft, as we know it today, is a whole different ball game, and the consequences of failure are much worse. Unless the thing is going to operate itself with no flying skills required on the part of the owner, it's a non-starter. That still isn't a trivial thing to achieve.
Then we have the fact that the EU are so worried about CO
2 emissions. If they think cars are bad, try aircraft.

Any light aircraft remotely equivalent to a family car in terms of passenger carrying capacity will emit many times the level of CO
2.
Yes, "modern" light aircraft are, on the whole, quite old-fashioned in design but try to make them more efficient and you either have to build them with huge, unwieldy wing spans and fly them slowly at low altitude, or make them capable of climbing to high altitudes quickly with all the complexity of pressurised cabins and turbine engines.
Aircraft really only work on a larger scale than the car.
Then there's the noise if all traffic took to the skies..
I'm not saying it won't happen, but it won't with current aircraft technology. It would take a breakthrough of similar magnitude to the discovery of powered flight to uncover a technology that would enable it, IMHO.
I agree that things have stagnated, though. The achievements we've made since the first cars and aircraft have been largely due to people doing things "because they can", knowing that there will be huge advantages and spin-offs that makes it worthwhile. Modern bean-counters don't allow people to do things "because they can" any more.
