I dodnt say masturbation is unhealthy, I think its fine. Masurbating a lot can also be fine. But the intent determines if its healthy or unhealthy.
What I said was, procrasturbation is unhealthy. Just like eating because youre depressed, or drinking because youre lonely. If youre just doing it to get the endorphins, its not much different to any other substance or behaviour that can be abused. And its indicative of a coping behaviour for some underlying problem that isnt being constructively addressed.