As an example, my 2017 Corolla runs the fuel pump for a while 5 hours after shutdown to test fuel system pressurization. I didn’t even know until I recently started parking it inside and I finally heard it running.
I think if the Tesla had been avoiding a hazard, there would be a lot more gray area for FSD to hide in. It’s true that sudden braking and swerving is sometimes the least-bad thing for a driver to do, but if a human driver showed a pattern of repeatedly performing that maneuver for no reason, at some point a reasonable person would have to conclude that that driver is at least partly at fault for the inevitable crash that happens.