Well, isn't it just like many other rules that most people don't give a !@# about:
-Carry on size restrictions
-Number of items brought on board
-Group boarding
-Turning off certain electronics at certain times
-Seat reclining
etc.

At least, I think, it is better than nothing and for a few people it will make them think twice before flying.
Of course others will just click "no" to all the questions in the questionnaire without even reading the question.

Personally, I would hope that the group that thinks twice is the majority, at least a slight majority. Just some wishful thinking here.