@IanW
Perhaps it is time to tell airlines that briefing SLF particularly the SLF that need to be told how to do up a lap belt may mean making things a little more formal.
I value your posts, but I think you may be wrongly blaming marketing, here. Think of the last time you sat through a "formal" safety briefing: how many pax were attending? Mostly people who could quote it all, anyway, I suspect. Now sit through a cheesy Air NZ briefing (my favourite is the Richard Simmonds aerobics one): quite a lot of people watch. It's the same principle as a workshop putting a pin-up next to the safety poster: before the people will pay attention to a warning, they have to have seen it. Some methods of attracting attention are no longer acceptable (and I understand why), but pax haven't signed on to join a disciplined service, and while we all ought to behave and co-operate, there's no requirement for formality. The warning about not taking bags should be more emphasised, I agree (Now listen up, you mo-fos, no mo-foing bags).