Firstly totally agree that whether or not the a/c is fit for flight is down to the Captain/Engineer(s) etc and not unqualified SLF.
However perhaps the mistake that is being made is to believe that we are in the "transportation" business. I believe this is a mistake the US airline industry made many years ago. In any business you are, actually, in the people business. These matters are very much a question of communication and how you treat the "customers". Obviously hysterical media coverage of minor events does little to help these situations.
"Establishment of rapport" starts well before the pax getting on the aircraft but as flightcrew we are very much the missing link when it comes to keeping pax fully informed. I do not think there are any simple answers to pax who behave in this manner but it is very much a question of how these incidents are handled (this is, I emphasise, no criticism of how this crew handled this situation) rather than the "logical" facts.