An NTSB investigation is a separate thing from an accident investigation for fault or insurance purposes. The NTSB does not investigate a drunk driver, that does not mean the drunk driver would be free of fault or charges.
People would be less upset with the drunk driver and more with the beer manufacture if they had been imbibing "alcohol free beer" which actually was not alcohol free.
Most other systems are far less clear, IMO.
Please don't propagate myths about "Tesla doesn't make it clear that you have to be in control of the vehicle."
My AP has many times disengaged because despite paying attention to the driving I wasn't putting enough torque on the wheel to convince AP that actually had my hands on the wheel.