If you look up “OCD” in the dictionary there’s a picture of a cockatoo (looks just like Elvis). They invented the word obsessed
In think I already said this (?) but a few broken feathers isn’t the end of the world IMO but there is always a danger with those big blood ones. A fully feathered bird has protection for those feathers because the other feathers. Once a bird has lost a whole bunch (like a tail or clipped wing) those new feathers stick out like a sore thumb just ready to get broken. That is when this kind of play becomes dangerous.
We weigh the good against the bad. There’s always a compromise. Modifying the way he plays with the hat as much as you can is a good one.