What could possibly go wrong?
This isn’t going to happen. The entire liability will be on ‘the software’ meaning a few accidents will bankrupt entire companies.
I'm thinking it couldn't likely be much worse than what we have. Most people, honestly, are just not capable of safely driving a vehicle anywhere near other people. Now... If I could have an autonomous-mode car and use of a special high-speed lane where my car would "plug in" to a system that let those cars move together in high speed drafting groups at 100mph+... I'd be all over it. Could move quick and still get great gas mileage. :-)