The data is suspect at best and should require a third party evaluation. I'm speculating that the reason for that 40% safety improvement is more a result of the difference between where autopilot can and cannot be used. People with autopilot equipped Tesla vehicles get the option because they likely drive more highway miles where it can be used mile after mile. Those who don't, likely don't and may be in statistically more dangerous driving situations like short commutes over high speed roads. When I commuted to the office, I'd pull out of my 25 MPH subdivision road and immediately accelerate to 65-70 MPH onto the highway and proceed to drive two miles. There's no reason for autopilot in those conditions so I wouldn't purchase the package, but yet making a left-hand turn onto a five lane highway where cars are regularly traveling at high speed is one of the more dangerous things you can do while driving for which if I got hit in a side impact could easily be killed and because of the location on a highway, would be counted as a highway fatality.