Theodore Henderson is one psychiatrist who takes physiological causes seriously, and has had remarkable success in treating ME/CFS with antivirals in adolescent cases mislabeled "treatment-resistant depression". He is not a psychobabbler. He is both an MD and a PhD. Henderson is one of the few doctors pulling people out of the psychiatric wastebasket after they have been thrown in.
It happens I have just had an argument about him with a respected local psychiatrist over a local teenager previously diagnosed with POTS who committed suicide by jumping off an airport parking garage. She was a high-school valedictorian who had gone on to M.I.T. Despite the POTS diagnosis, nobody had warned her about getting worse if you push yourself when you have orthostatic intolerance, or about making very bad decisions when your brain is starved for oxygenated blood. I consider this a clear case of malpractice. Waiting until the patient goes to a psychiatrist for "depression", following predictable multiple setbacks, risks exactly this type of misjudgment leading to unexpected suicide.
When the pilot of an airplane makes a serious error while suffering from hypoxia, you don't normally attribute this to deep underlying emotional problems requiring psychiatric treatment, you concentrate on preventing hypoxia. Why should cellular hypoxia as a result of episodic cerebral hypoperfusion be classified as a psychiatric disorder?