Why is it that so many of the PhDs and MDs out there are unable to tell when someone's lying to them about their very own areas of expertise?
Either they're not that smart or the processes aren't very good -- though no single researcher is responsible for their field's poor processes. Either way, we shouldn't assume that any one PhD or MD recipient is an expert until something changes. Degrees, on their own, don't signify expertise or credibility.
The standard of evidence in medicine research generally is really poor. Most of the papers have serious problems and reach to conclusions they can not defend. Worse is huge areas of medical research are full of fraudulent research, almost all of Psychology and Psychiatry is atrociously low quality studies and they rarely replicate even then. There is widespread corruption around the sale and adoption of treatments and the entire system of peer review and journal acceptance is almost exclusively based on the authority of the main author and not on the value of the paper.
In short medical research is nothing like Physics or other science papers and endeavours its evidence base for most of what it already does is often severely lacking.
Either they're not that smart or the processes aren't very good -- though no single researcher is responsible for their field's poor processes. Either way, we shouldn't assume that any one PhD or MD recipient is an expert until something changes. Degrees, on their own, don't signify expertise or credibility.