It has killed people letting it self drive on the freeways. It was a while ago and maybe it has gotten better since, but I don't think taking your eyes of the road is advisable.
The latest update has eye tracking and warns you if you take your eyes off the road for more than a second or two.
Nobody is saying that self-driving cars are perfectly safe. Considering how many Teslas are on the road and how many miles are driven on autopilot, it would be surprising if there weren't any deaths. As long as it's safer than unaided human drivers (which it is), it's a net win.