There is no doubting that some engineers are, or can be, stupid - in the same way that some "Quality" personnel (me included) can be accused of being shut up in ivory towers for too long and develop a sense of wellbeing by dictating what should be done through e-mails, megaphones and publications that most shop floor's have ceased to read many years ago.
There is nothing like a practical way to prevent someone doing something and writing posters isn't always the way to do it.
AD's were purely introduced to mandate the acceptable (not always correct) way to manage something. Laws do the same. And if ICAO, FAA, EASA, the blessed CAA or even Commerce cannot see the safety issues in not enforcing this as they have done for the drivers of aeroplanes and HGV's, then why should anyone volunteer to reduce their incomes to placate this seemingly weak proposal?