This probably isn't going to happen.

Getting to level 5 will require "V2X" technology - vehicles communicating with other vehicles and the road/traffic infrastructure itself.

We will need a forward-thinking government to start building sensors and communication tech into roads, stop lights, parking spots, and a secure/interoperable internet for all these sensors to communicate autonomously.

Currently the cost of implementing such a system is way higher than the return to drivers who can...what, work on more powerpoints or facetime while they're in the car instead of driving? Not to mention the huge security and safety and liability risks this would open up.

That's why we solved this problem with public transportation in the past - hire one person to be the "V2X sensor" AKA bus driver.

Not really more expensive. If we have x deaths per year..let's say 10k for easy math. Over a decade that's 100k people dead. If self-driving cars can bring that to 0..that's 100k more people in a decade able to pay taxes because they didn't die. It's 100k families that maybe didn't lose their primary bread-winner and don't need to live off government assistance... So there's economic value in less people dying. It's also less in medical costs. Imagine what the bill for medicare for all would be if there were 0 traffic accidents across the entire U.S.A? Not to mention it could ease up congestion and make changes to the way they do construction or how often by maximizing speed and travel to make roads last longer somehow... Also less need for police to monitor traffic, I'm sure we get that sort of grid we'd also have a lot more big brother surveillance baked in too to make police jobs easier. Which I guess is good/bad depending on which side of the privacy ethics you are on surveillance and how 'honorable' our government is at the time (hopefully more honorable and less like china and it currently is)....