In case members agree with the above 'impression' I'd like to state the 'facts' I reported in my post #44 happened, according to my log book, before 9/11....it occurred on 26 Aug 1987. My only correction is the flight was predicted to be 8 hours (not 10 as I casually observed) and actual time was 7hrs and 54mins.
Prior to joining an airline I was an officer in the Royal Air Force and crewed the VC10 with passengers like the Queen, Prince Charles, Prime Ministers Wilson and Heath...and many other dignitaries, and yet, couldn't afford to fly commercially with my own family, and never did.
It has become so inexpensive today almost everyone can afford to fly.
During my airline career passengers understood how to behave (my story post #44 was an exception) but today, when I get on any budget airline like Lion/Air Asia, some passengers just don't know how to behave appropriately.
My impression is it's that inappropriate behaviour that causes many problems leading to events discussed on this thread. Airlines, to keep costs low and seats full, load passengers like getting on a bus or train and behaviour is conditioned on that premise.
For example.....I'm amazed airlines allow the cabin baggage I see some people have on their backs...don't those people know every time they turn they swipe another person! Also...some people think boarding the aircraft is timely to start long conversations with their friends 6 rows away....and some demand the Flight Attendants for the 'password' and chatter on a phone while being given instructions over the PA.
I've heard a story of passengers firing up a picnic cooker to heat their own meals....

...and I know some steal the lifejackets...that's why I always check under our seats after boarding.
Airline advertising is another culprit...they seem to advocate that transport by aeroplane is a joy to behold...ever see the advert with Jennifer Aniston preferring to sit in economy rather than the first class she can easily afford...some people believe that shit and are underwhelmed when getting on any flight with seats smaller than their arse and observe Union flight attendants, hips wider than the aisle, that they have to move sideways....
It's more than a working-class person like me can take....and some blow up.....and others take selfies of incidents. I'm thinking of learning how to take pictures on MY smart phone...so far I only know how to say hello!