All cars were once restricted in the locations they could drive. EVs are restricted today. I don't see why universal access is a requirement for a commercially viable autonomous taxi service, which is what Waymo is currently. And the need for human operators seems obvious for any business, no matter how autonomous, let alone a business operating in a cutting edge and frankly dangerous space.
It's by definition in terms of how these things are counted.
L4 is "full autonomy, but in a constrained environment."
L5 is the holy grail: as good as or better than human in every environment a human could take a car (or, depending on who's doing the defining: every road a human could take a car on. Most people don't say L5 and mean "full Canyonero").
> or, depending on who's doing the defining: every road a human could take a car on.
That's a distinction without a difference. Forest service and BLM roads are "roads" but can be completely impassable or 100% erased by nature (and I say this as a former Jeep Wrangler owner), they aren't always located where a map thinks they are, and sometimes absolutely nothing differentiates them from the surrounding nature -- for example, left turn into a desert dry wash can be a "road" and right not.
Actual "full" autonomous driving is crazy hard. Like, by definition you get into territory where some vehicles and some drivers just can't make it through, but it's still a road(/"environment"). And some people will live at the end of those roads.
