Despite the tone of the OP, I think it has usefully raised the question of how best to get safety information to passengers. I try hard to listen to the safety briefing, but the modern airport experience tends to turn my brain to cream cheese, so I find I do sometimes miss bits.
Bealzebub said
It would be quicker to say, "listen carefully because your life might depend on this in a few minutes." However it is deemed more sensible to adopt a low key, more professional, and courteous approach.
This is a tough one. A low key approach full of euphemisms ('in the unlikely event of a landing over water') will prevent panic amongst the passengers in relation to a very unlikely event. But it doesn't give people a reason to pay attention. Scaring the bejaysus out of them - 'if the plane crashes, we'd like to help get as many of you out alive as possible' - might just get some attention.
Or perhaps airlines need to find some way of getting passengers involved in the process. How about a scratchcard with the locations of the emergency exits on, with one winner per flight?