More complex than that, let's say your car state it wasn't on autopilot when for "unknown reasons" a pedestrian was hit: how can you prove you are right, the car was indeed in autopilot mode, you try to avoid the impact, but the car does not react to your actions?

So far 99% of cars have purely mechanical breaks and steering so even without assistant systems A BIT you can act, but very few start to be "by wire" (like Tesla Cybertruck with the famous "lagging steering")... Ownership is more vast then "just my files on my desktop storage". Similarly try recalling the recent "Google position scandal" wrongly accusing some people to be on a crime scene. Materially it's still some data in some file but...