I believe there have only been 3 - 4 deaths in tesla's cars where people have been using autopilot and then they have been given multiple warnings before the accident (with the exception of the semi truck that turned in the road in front of the car, confusing the sensors, leading to the accident"
Given there are something like 34,000 road deaths in the USA every years thats a fairly impressive record.
Obviously as more cars have the technology it will get safer, especially if the cars are able to talk to one another and know where all the adjacent cars around them are, their speeds and directions/route, it would more or less eliminate collisions.
It doesn't obviously stop accidents where people or animals walk out, but volvo have an impressive track record with their technology of being able to identify animals and people as well as crowds and assess if something is likely to enter the path of the car long before the driver would be able to make that decision.
The biggest set back was Uber who killed that lady a few weeks back because the software engineers had turned down the sensitivity of the system to make a more comfortable and smooth ride.
Basically it was ignoring more hazards to prevent the car braking and accelerating as often, leading to it ignoring a woman crossing the road in full view of the sensors, that should have been much safer than the eyes of the driver.