This quirk in our nomenclature has similarly bothered me, having lived both East and West USA (New York, New Jersey, turnpike and toll bridges, truck driver there, and California, born and returned; I still call "Fastrak" "EZPass").
Freeway in the West means divided with full speed on and off ramps but absolutely no stopped traffic of any sort, entering, exiting, turning, crossing, or anything. Of course, as with everything good and holy, the bastard Communists have corrupted that with failing to expand capacity (causing slowdowns while driving) and "meter lights" (which only metronome cars onto the freeways one or two at a time by making them stop on on ramps, an otherwise illegal thing to do on our freeways). This is using the word "free" to mean free of stopping, free of obstructions, free of pedestrians and bicyclists, free way, free of problems. It's almost a bending of the meaning of the word, and has long caused confusion. But, freeway sounds like a nice word. I'm in favor of toll roads for road maintenance, but not for income redistribution, and the commie government wants to primarily use tolls for income redistribution. But I'd love all our freeways being proper toll roads and still called freeways, if it means making them free again (of stopping).
But I don't know what the Tesla rule is. They used to be actually incorrect, referring to freeways as highways, when our California driver code clearly defines highways as not freeways. You often see signs saying "End Freeway, Begin Highway", which in code, practice, drivers' education and common use, means possible cross traffic and any type of stopped traffic control (lights, yields, stops, etc.) on a fast road, and possibly undivided, and even possible bicyclists and pedestrians. At least Tesla fixed that egregious error. The nomenclatural confusion you refer to is actually worsened for you a slight bit by their improvement of their terminology for us.
I'd prefer if they were much more specific, but I suspect they have the usual issue that their lawyers and liability concerns greatly lag their AI team progress, and that even their AI teams don't know how far the AI has or has not gotten. Clearly they could draw some better conceptual lines, though (oh no, I don't think I said that clearly).
