Long-distance goods transport with trucks is such a ridiculous concept, it's really time we just face it: it only ever made sense because the state funds the roads and road repair from general taxation, we have ridiculous subsidies for the fossil fuels that make it run and trains had the misfortune to be invented such a long time ago that the government has suffocated the industry.

Rolling resistance is somewhat of a rounding error, by the way. The big killer is aerodynamics: the power needed to push air out of the way increases quadratically with speed. But there is a cheat code: if you make the vehicle longer or add something to the back, it can ride in the slipstream. Only you can't make trucks very long at all because they need to work on public roads. Trains on the other hand can be made ridiculously long, saving massively on energy - multiple miles of wagons if you so wish.

Really? I was under the impression that this was one of the primary benefits of standard shipping containers.

https://en.wikipedia.org/wiki/Intermodal_container

I think you're grossly underestimating how spread out truck destinations are. You would have to have a very extensive rail network to get cargo anywhere near all the destinations where it's currently trucked. And if the rail network doesn't fall within X average distance of every destination, the value proposition of this idea rapidly becomes negative.