I like your post, but it's just one (I suspect minority) perspective.
Why would you ever want to take that experience from me and give me the empty, bored, unchalleneged feeling of sitting in a plane or train, not in control of any element of the trip, a passive object sitting there and rotting? Why would you want to take active growth and engagement and replace it with the need "to kill time"?
Well, because I don't have enough hours in the day to do the things I am supposed to do already. And because any time I want to visit someone or something from my home I have to kill 5-8 hours staring at the same highway I've stared at a thousand times before. I also have to risk my life because it's one of the most dangerous highways in the world. Because after the hundredth time doing this, driving irrevocably became a chore. I think you live in the east, yeah? Remember that. Driverless cars were fucking made for the great plains.
Am I going to use the driverless mode on a beautiful country road? (maybe -- I like to be able to look at everything I drive by without hindrance) --but probably not. Am I going to use it in the city? Probably not ... unless, wait, there's tons of traffic like there always is; I can't stand driving in traffic, no one can.
Another point: I get the meditative feeling as much as you do -- but some people get it and fall asleep. Cars simply aren't safe.
ad absurdum: someday we invent teleportation. Great! 95% of the time I'm going to use it. But the 5% I don't will be the time I spend traveling, looking at things, etc -- and I'll value that time so much more than I do now, because it's a luxury rather than a necessity.