"When you're looking at a terminal, a traditional freight train is about three miles long, which means you need a place to park three miles of a rolling stock. You need a buffer of about 300 containers. You have trucks going back and forth. It's a big operation with a lot of real estate and a lot of cost. Our vehicles can interface like a semi truck to go directly where they need to go, load and unload you to get out of the way," Howard told me.

So just... make a shorter train? You can make trains more flexible without going down to "each car has its own motor". The only reason why freight trains are so long now is because the companies wanted to cut costs by reducing the number of drivers (even though this comes at a cost to safety and worker well-being). Of course, they need to believe in autonomous rail cars so they can fantasize about automating away their need for workers instead of just employing more people.