Are regular cars useful? A self-driving car is just as useful for someone who can't drive: minors, many seniors, many people with disabilities - or people who just don't have a driving licenses, like me.
For them, a 30km/h crawler with overattentive collision avoidance system may well be useful. This is not much different to how public transport drivers have to drive.
I expect them facing same issues like trams and trolleybuses - terribly bad experience in traffic.
You only see risky people aggressively trying to overtake and scratching their paint, while leaving the driver no opportunity to move an inch.
A self-driving car is a mobile monitoring station; every such behavior will be closely tracked, recorded and possibly shared with the authorities. I think those drivers will learn to stay away from them.
Are regular cars useful? A self-driving car is just as useful for someone who can't drive: minors, many seniors, many people with disabilities - or people who just don't have a driving licenses, like me.