I think longer and more complex PSAs can work in situations where people are likely to be paying closer attention. Hurricane prep in the hurricane belt during hurricane season is a good example. When I discussed it before, I was talking about PSAs directed at general audiences, with no particular news peg. It's not that people are stupid or lazy, it's that people are busy. If they don't have a specific and immediate reason to pay attention right now, it's unrealistic to hit them with anything other than something very simple and concrete.