I work for a logistics company which operates a hub-and-spoke network of trucks running between its branches in the US and Europe. Think just like an airline running scheduled flights, but with trucks going warehouse to warehouse. The truck is contracted out to a service provider, and goes on schedule regardless of what is on it at the time. The reason we do this is because it offers a predictable way of getting stuff from point A to point B using existing infrastructure. And 99 times out of 100, with the volumes we move, the truck is full of something. Or many somethings.

And when you move the volumes of freight we do, that helps us fulfill our business case, which is "give us your stuff. Here's the paperwork saying we take responsibility. We'll make sure it arrives at point B on time, compliant with customs and all import/export laws, and compliant with all your industry's off-the-wall niche requirements, without you having to do so much as think about it anymore."

This isn't feasible using only rail without multiple governments across the world investing billions or maybe trillions of dollars/Euros in new track. Especially in America, where the rail network has always gotten outcompeted by truck freight for many different reasons. What you're describing is a pie-in-the-sky ideal, not what's necessarily feasible without making freight prices skyrocket due to high rail demand, low capacity, and the probably 25+ years it would take to change this. If not 50-100 years.