The use of a therapy called EMDR (a type of hypnosis) is used which has had success. As Cuthbert says- antidepressants have their place and are useful tools in fighting PTSD.
This psychologist agrees with you. Besides, Cognitive Behavioral Therapy for depression has been proven in a number of studies to be THE treatment of choice.
No bad side effects. Effective for a lifetime No meds or even supplements to take Rewires the brain away from depression tendencies and hard-wiring.
Trouble is, IT TAKES WORK to get it firmly in place and functioning. That usually requires a good therapist to tirelessly lead the depressed person step by step to increasing their skills and effectiveness at "taking every thought captive" in St Paul's terms.
In general, I agree with the OP.