Same. Ten years ago I was predicting that the long haul truckers would be the first major segment of the workforce to be replaced by AIs. Turns out it is going to be junior devs and entry level artists. Oops.
Highways are simpler on paper, but it turns out that any crazy thing (pedestrians, obstacles, etc.) that happens on a city street can happen on a highway, so you have to be ready for that. Energies are many multiples higher at highway speed, so "contact" events are much more serious.
The solution for this is to make it so the cars physically can't go everywhere they want to go. Meaning, instead of a highway designated for freight, use a rail.
My guess is we don’t have any current infrastructure for outside the city depots. Right now trucks pick up the cargo after long distance shipping and take them straight to their final destination. Setting up what you’re talking about would require a paradigm shift in how the trucking industry works.
My guess is that getting local permits is easier to get for Waymos (never faster than 45mph, only within bounds of a single city) than long haul cargo (on highways faster than 65mph, crossing multiple city boundaries).
That’s true in AZ. Waymo is not allowed to operate on freeways yet