the human animal is far too stupid, lazy distracted and "disconnected" for it to be ever viable beyond being full autonomous...hell most ppl on the planet dont even know what a manual trans is anymore let alone how to use one.....flight?..oh hell no
the average joe cant even be bothered to check the oil, and when was the last time you saw the average joe change a flat tire vs calling a company to do it, or hell check the brakes or tread wear..
the thought of ill maintained rigs falling out of the sky suddenly becomes all too much of a reality, and lets face it, with tuners and such hacking into the programing it wouldnt be much of a stretch to overide anything that said "X is broken your not allowed to take off" .....even the teslas have been hacked and options "unlocked" via users
the idea is valid, the prototypes have been badass over the decades....its the human element that fails