You are wrong. Pilot in command[1] only qualifies when the plane is in flight, which is even mentioned in the quora question you linked. In flight definition requires plane to be moving under its own power. Additionally, the pilot did not tell the passenger anything. An on the ground manager did.

You have no idea what you're talking about. Please throw away your throwaway account.

https://en.wikipedia.org/wiki/Pilot_in_command