I'm looking at this from the point of view of a car buyer, and I don't see a good reason for me to embrace smaller cars. Right now I drive a 2008 BMW 328i (I'm not showing off - they're not expensive) and it's too small. The back seat is uncomfortable, the trunk is tiny, and the fact that the car is so low to the ground makes it hard for my older relatives to get in and out. But my car is a foot and a half longer than the Chevy Bolt which the author likes.
I like my car because it's sporty, but if I was a more normal car buyer (someone concerned about practical utility rather than about going around corners quickly) I would definitely buy a bigger car.
I'm also not convinced that EV range isn't important. Most of my trips are less than 30 miles long, but several times a year I do go on a long road trip and I wouldn't buy a car that didn't let me do that. I wouldn't even consider a car with a range less than 300 miles unless I also owned another car with a longer range. A range less than 400 miles (still shorter than my gasoline car's range) would be a major downside.
You don't need a car for your long trip. You need a working high speed rail network.
The idea of "embracing smaller cars" is 30 years out of date. You needed to build the infrastructure to provide transportation so that it gets unnecessary for you to own a car.
I usually vacation in rural areas and it wouldn't make sense to build train routes there, but even if I were going somewhere by train, I would still want to have a car once I arrived. (A place like NYC might be an exception because there's nowhere to park unless you're staying on the periphery.) I suppose I could rent a car at my destination, but I think having to do that would be more expensive and less convenient than just owning a long-range car.
I've heard Europeans talking about how great their rail network is, but I'm not convinced. I've never used it myself so maybe it's better than I think it is, but here in the USA I prefer to drive even if there's a train straight from where I am to where I'm going.
(I know there are environmentalist arguments in favor of trains, but I'm not addressing those here - I'm only talking about what I want, not what I might be obligated to do.)
As one of those Europeans I can assure you that having a working train network is great. But again: That's not the situation you're in, so I completely understand your decision.
The change we need to see in regards to the environmentalist arguement you're mentioning, will only be successful if the option to take a train and rent a car close to your final destination is more convenient or faster or cheaper or all of those for you.
It's the way we build the world that decides what is the best way to travel. We should build better worlds, not better cars.