And that's the very part of our society that falls into the category of "not sustainable". Even if we have practical EVs in the future, the sheer expense per person of maintaining low-density living will mean its end. And climate change may mean that much former farmland which is now suburbs will have to be returned to its original use. Like it or not, unless you're a farmer, I see an eventual end to the spread-out living many people are used to for these and many other reasons.We have built a society in which I cannot practically function in without something like a car. My work is 15 _miles_ from where I live. The nearest "3rd place" to hang out is 5 _miles_ away.
I'd love to have a more efficient car, but most of us cannot negotiate a city built the way ours are without one.
We need to use mechanized transport far less, especially mechanized personal transport. Long term that will likely mean large population increases in existing cities which already have decent public transportation. I can easily foresee NYC going from 8.5 million now to 50 million by 2050. Provided we build more new subway lines besides the Second Avenue subway, handling that many shouldn't present a problem. There is still plenty of land in the outer boroughs which is underutilized. Just getting rid of the two local airports could provide room for several million people on prime waterfront property, for example. And I have little doubt that in time personal autos will be banned at least in the borough of Manhattan, perhaps even city-wide. Given comprehensive enough public transport, they just won't be needed. The streets could be narrowed for cycling only, and more housing built in the reclaimed space. In the closer suburbs of NYC which likely won't be abandoned, such as Nassau/Suffolk counties, parts of New Jersey, Westchester, etc, we'll probably need to roof over highways and railways to provide more land for housing.
Nationally, I can foresee a need for a high-speed intercity ground tranportation system, be it either maglev or conventional rail. Airplanes are no more sustainable in their present form than autos. And airports waste a tremendous amount of valuable urban real estate.