You should see my 2004 Nissan. First year infinite rock chips on the hood. Maybe I drove too close... 6 years old spot on roof deteriorating. Now entire roof and some of trunk most of the paint gone.
Thought I polished too much but all the others one the road are identical or worse. Hours of paint protection was a waste.
Hood looks far better. It was replaced due to deer hit and painted by a friend 17 years ago. One would think factory would be best. Nope.
So I'd agree JDM clear coats are too thin or all paint is inferior compared to others.