There's an approved map because the approval process requires the manufacturer to specify both areas and conditions they are applying for, and documents supporting that the vehicle is ready to be operated autonomously in those areas and conditions (which doesn't just include technical readiness, but also administrative readiness in the form of things like a law enforcement interaction plan, etc.)

> like i get having a pilot somewhere but once that goes well (and we're way past that point), why isn't it just blanket approval everywhere.

Because “everywhere” isn't a uniform domain (Waymo is kind of way out in one tail of the distribution in terms of both the geographical range and range of conditions they have applied for and been approved to operate in, other AV manufacturers are in much tinier zones, and narrow road/weather conditions.) And because for some AV manufacturers (if there is one that can demonstrate they don't need this, they'd probably have an easier lift getting broader approvals) part of readiness to deploy (or test) in an area is detailed, manufacturer specific mapping/surveying of the roads.

My question is why they even have to apply for specific areas to begin with? Just approve the manufacturer for certain conditions and let them operate wherever they want.