Knowing doctors, this comes down more to Hanlon's razor. Many don't know any better and have a poor grasp of the scientific method. For many being a doctor is

Knowing doctors, this comes down more to Hanlon's razor. Many don't know any better and have a poor grasp of the scientific method. For many being a doctor is more of a trade than a profession. Their scope of work is too broad and they're far too busy to keep up. As a result, they're perhaps even more susceptible to marketing than average people. They don't have time to dig into pubmed and deeply understand something they see (generously) 1% of the time. They have to rely on people who otherwise get paid to do the research. If there's no money to be made from a treatment, it won't be able to donate to universities, fund studies, or pay for advertising. Doctors won't hear about it.