It would be great if everyone would be found to have a disorder.
I have an "autistic spectrum disorder", and I don't consider it a disease, I consider it a brain/personality category.
Therefore, the term "disorder" to me implies that I don't fit in some order made up by people who don't know anything about me, who I have never even met.
If everyone would "have" a disorder, it would be an acknowledgement that the order they made up, isn't.
There is no order, everyone is different. No matter what kind of label is stuck on you by people who think they know everything, you are the only one who can truly know and help yourself.
But the lack of understanding of self, and feeling powerless to work on their problems, leads people to search for causes and solutions in the wrong places, like prescription/illegal drugs, doing their best to stay as much as possible in the victim mentality, materialism etc..
PS: yes, I know some drugs can be beneficial, but psychiatric drugs are mostly about symptom suppression.