The current generation of self-driving cars is fairly impressive already, but what I'd like to see is a city full of them. I have a feeling that self-driving only works as long as the majority of drivers are human drivers. It's trivially easy to come up with traffic situations that could lead to a deadlock by blidndly following the rules.
Humans will use hand signals, eye contact or someone will violate the rules a little or make way when they don't strictly have to in order to ensure that traffic flows.
I think that car-to-car and/or car-to-road communications will be required before large scale deployment is possible. And I have not heard from a cross-manufacturer effort of creating a protocol for such communication.
Although I do understand why the automotive industry is hell bent on getting their level 2 autonomy out there. Money from the customers is needed to keep the R&D effort going.
I personally did not understand why anyone would want a Level 2 car where you have to be constantly on the lookout until I visited Silicon Valley and drove a stint on US Hwy 101 in rush hour. And I guess this is the initial target market for the self-driving car industry: wealthy individuals who have a stressful morning commute in stop'n'go traffic. Money from these early adopters will go to funding the R&D for the next generation in the hopes that Level 4/5 will some day become reality.
But in my conservative estimate, that's still years away from being adopted en masse. There may be a significant minority of them on the road in 3-5 years but I can't imagine it working very well if they were in the majority.