Accidents involving self-driving car features are inevitable. Yes I always say self-driving cars won't work, but cruise control+ type features do exist some and presumably will get better and more elaborate, whether or not that's a good idea. What won't work is the fantasy of a completely automated system operating within a fleet of those old-fashioned cars. What did we call them? Oh, yes, cars. The push a button to summon it and tell it wherever you want it to go version.
Oddly I don't think think safety is really the hurdle. Sure it'd be easier to make these things if safety wasn't a concern at all, but programming them not to hit things or be hit is probably the easiest thing to do, even if that is unlikely to work perfectly either. I just don't think they'll work as promised. They'll do something, they just won't do what their proponents claim they will do, or anything close enough to it. They're the next Segway revolution. What they can do is neato, just ultimately not all that useful.