I agree that Tesla is using the term "autopilot" opportunistically to say the least. Whether the term accurately represents the feature they want to promote (imho technically it does, but more on that later) is becoming less relevant.
But I'd like to bring counter-argument to your points (a) and (b): taking away the autopilot feature from both airplanes and cars, an airplane pilot still has to undergo substantially more training than a car driver does, so imho the increased training for pilots compared to vehicle drivers is largely coming from the difficulty in controlling the machine and the more deadly consequence of control-loss to the driver / pilot and to the others.
That being said, the term autopilot is being used opportunistically. There's no way Tesla will back away from the term now, so the next best thing is to warn the user, in every step of the way, that "YOU HAVE TO KEEP YOUR EYES ON THE ROAD IDIOT", to the point that if they can detect your hands not on the wheel a warning sounds.
I do believe the Tesla Autopilot and the autonomous mode in the future will save lives, what we're experiencing is the growing pain till we get there.