There is definitely a lot of room to criticize the behavioral side of the mental health world. There is even a growing movement to through out how the DSM 5 is used based on growing evidence that there is no such thing as a singular mental health diagnosis. For example, people suffering from schizophrenia have been successfully treated only to then commit suicide because they were also suffering from depression which wasn't treated. Thus, using a manual to diagnose and treat is inadequate because people with mental health issues almost never suffer from a single, monolithic issue. Mental health problems are more like a broad continuum of interrelated problems.
But there is a ton of science behind psychiatry and they are deserving of the Dr. I have seen psychiatric intervention be the difference between life and death. My wife's uncle was in Vietnam and probably went through most of his life with undiagnosed PTSD. He was a photographer for Stars and Stripes and was always on the front lines taking pictures of the dead and dying. After nearly killing himself with alcohol, he finally went and got treatment with a VA psychiatrist. Within six months, he stopped drinking, reconciled with a bunch of estranged family members, and was finally able to deal with his war experience without harming himself or others physically and emotionally.