Cattle truck, that is a wrong reading of the automotive world. The GM and Ford engineers told me in 1985 when I was consulting, that their response to fuel prices would be to use little engines and turbo the hell out of them. The technology has been around for a long time, it’s just that the market didn’t want to pay for it at the time.
If we have a battery chemistry breakthrough then drones. Otherwise forget them as people movers.