I think you’re right, overall, to be skeptical of this project, which is so like so many other dead projects before it, for several of the reasons you list.
But: Did you know the first autopilot - for powered, heavier-than-air, fixed-wing aircraft - was invented 106 years ago? That the first automatic trans-Atlantic flight, from takeoff to landing, was 71 years ago? A very high degree of autonomous flight has been a reality for many years. Autonomous flight is a much, much easier problem than autonomous driving.
Vertical-landing craft like helicopters also have some special abilities where dealing with catastrophic failure is concerned. When automobiles were adopted in large numbers, they were a lot less safe than modern automobiles are; I don’t think the barrier to entry in the safety department is likely to be as insurmountable as all that.
