Eventually, I imagine all passengers will have to fill out a validation because as silly as it sounds it may have been or certainly will be an issue for litigation in the future.
The crew have a legal obligation to ensure that pax are made aware and surely there is a legal onus on the CC, the fact that people choose not to listen or fail to comprehend is not relevant in todays 'Health and Safety' and litigation mad mode.
Reading through the thread all of us are aware that most of what is contained is a snapshot of what takes place. Many people that do listen probably do not understand what takes place irrespective of what the Captain says. CC often go thru the exercise with a less than enthusiastic outlook which may also be detected by the pax.
Simply there is no answer it is a little like car / driving safety. If you take out your user manual it will tell you to check up to 25 + items every time you go out, I know no-one that does this and many drivers some with the best cars are probably the whorst having little knowledge of where when and how to do these things.
From pax perspective that seems to be how they view or otherwise the safety drills.