I used to struggle a lot, when I was a teenager I used to cut my own hair because I hated it
I doubt he really is worried about his ears getting cut, but its more of an excuse to try and get it to stop, its hard to explain why you dont like it, but saying there is something dangerous helps him justify to others when making him feel he is strange. He just doesnt like having is hair touched.
Distraction could work, but it might be better to try and NOT make him feel strange for not wanting to have his hair cut, explain that its ok not to like it and other people dont like it as well, but its something that has to happen. It may feel like the dentist drilling away for him and does it really matter if it takes an hour to get your hair cut, if he has ADHD then hell probably make up the time somewhere else!
Its better to accept that its normal behavior to not like another person to cut your hair than try and make him feel isolated and strange in my opinion.