Reference passengers interfering with controls, in the event of an accident and injury etc the pilot may be able to take a civil action against the passenger who interfered by proving that such action precipitated the accident.
To turn your argument on it's head, if I were flying in the RH seat with you and you pranged the a/c even after I had warned you about low airspeed/ insert frightening situation of choice, and I didn't take control and sat through the inevitable crash, would I have a claim against you? I would have an insurance claim obviously but if I pressed for damages in that I could have prevented the accident had you listened would that stand up in a court of law? We're not talking about pax here we're talking about qualified and current pilots. Would the court say 'Well as a current on type and qualified pilot Mr Wilson why didn't you take control?'