What if it was more widely accepted to use placebos in certain cases where diagnosis is inconclusive? Much of modern "vagus nerve connection/mind body" books o

What if it was more widely accepted to use placebos in certain cases where diagnosis is inconclusive? Much of modern "vagus nerve connection/mind body" books or childhood/adult trauma books talk about this phenomena of the pain "being in your head". There's also John Sarno's book about back pain. What about the untethered soul perspective by Michael Singer? I was a huge skeptic of this type of "healing" for my whole life. When I was extremely depressed and experiencing immense pain in my chest area on a daily basis for 14 months where cardiologists had no clue what was going on, I started to go through this "unlearning of the pain". Now that I'm on the other end of it, I feel like I have tools for understanding much of the pain/anxiety introduced by our mind.