He may only be 3, but I think it should still be his choice. Leave it as an option for him, my daughter proudly proclaimed she was Deaf at age 3 and didn't wear her aid for almost two years now she grabs it when she feels like it. But in the beginning she kept braking them, on purpose she didn't want to wear them! When I explained it was her choice she quit destroying them and they hung in a place where if she wanted them she could have them.
Nice. We need more parents like you.
I'm all about choices.