I think of it in terms of I am still piloting the vehicle, but FSD is executing the maneuvers. This means that I am able to focus on the bigger picture (looking further forward, paying attention to what is going on in all lanes, etc).
I am a MUCH safer driver with autopilot/FSD than without.
So, to your devil's advocate, I am sure I would blame myself if my family member died while driving my car no matter what the car was. But FSD in my car has prevented accidents for me and my family.
Edited to add:
I don't want to pretend it is without risks. My biggest fear with FSD/autopilot is that it requires a constant understanding of who is in control. And that is the thing I stress to my friends/family. Your #1 job, and the thing that can kill you, is thinking that autopilot is engaged when it isn't and running a red light or driving off the road on an interstate exit.
Tesla gave me a loaner for a couple days while my car was in the shop. The loaner did not have FSD, and there were a couple of times I expected it to stop and it didn't. It was mentally tough b/c it was familiar like my car, but it wasn't my car.