There was no net impact in that accident. It replaced three deaths which would have occurred without autopilot, so it was part of a net gain in lives.
Perhaps that particular human was special and worth saving over the other two who were saved instead, but I am not aware of any reason to believe that.
Only after a particularly tortured interpretation of highway safety statistics.
If you exclude pedestrian deaths (Few jaywalkers on the interstate), motorcycle deaths, deaths in conditions where autopilot cannot be used, and deaths due to collisions of lighter, less safe, older, or poorly-maintained automobiles, then regular highway death statistics start looking better then autopilot-enabled ones. [1] [2]
Again, there's a great gap between the hype of Tesla, and the reality.
Perhaps that particular human was special and worth saving over the other two who were saved instead, but I am not aware of any reason to believe that.