BIG conflict of interest… if someone goes on his show stating something like “brushing actually destroys your teeth, you should take X supplement which I developed and read my book” he gets money and viewers interested in this “no brushing” thing. If the conclusion is that you should brush and use toothpaste he doesn’t have a podcast.
He’s in the industry of going against “mainstream [ie scientific] knowledge”… which provides him and endless stream of salesmen who cherry picked scientific papers that support their schtick… and a lot of interested listeners who get an excuse for everything they don’t feel like doing (“oh, this guy on Rogan said brushing destroys your teeth, so I guess I’m better off leaving them alone”)