I would say people who are not as disabled as I am should not get a diagnosis. My condition is obvious. I was hospitalized several times and now I cannot work, I have one friend, and I am homeless living in a minivan.
I had one good PDoc who helped me, with my genetics, not to diagnose me, but to help me find what helped me and my specific symptoms. Diagnosis is not as helpful as looking at your own symptoms and own history and using that to find what helps you.
If you don't get the diagnosis before it causes a crisis, it can be _much_ harder to get appropriate support _after_ a crisis.