Obviously take with a grain of salt give the source but.. https://www.tesla.com/VehicleSafetyReport

"In the 4th quarter, we registered one accident for every 3.07 million miles driven in which drivers had Autopilot engaged. For those driving without Autopilot but with our active safety features, we registered one accident for every 2.10 million miles driven. For those driving without Autopilot and without our active safety features, we registered one accident for every 1.64 million miles driven. By comparison, NHTSA’s most recent data shows that in the United States there is an automobile crash every 479,000 miles."

Yes, people disengage auto-pilot (or it does so itself), but it is at least plausible to say that in this like-for-like comparison of drivers and vehicles self-driving is at least comparable in safety.