I'll stick my neck out. I reckon the guys who fly Air Force one respected by these who fly on it. So when the "Belts" light is on everybody's belt is on (including the Preseident) and when they hear over the PA or from any cabin crew "..therefore may I suggest that..." The listeners will follow the suggestion. I'll also not expect that any of the crew of this aircraft will ever be challenged by the passengers regarding the decisions they take before or during any flight. They may well have to justify what they did afterwards, but only to their direct seniors. And if we think about the Polish Tu-154 flight in 2010, it appears from anecdotal evidence, that interfering with or putting pressure on a flight crew's decision making process might not be a wise course of action.
PM