Trump has trouble with equivalencies. Because Dr. Oz was a success on TV, Trump thought that meant he would be popular enough to win an election. The two have nothing to do with each other. Trump, of course, is the exception to the rule. It was his role on The Apprentice that won him the 2016 election. His base just didn't seem to realize that he was playing a character, that he wasn't, in fact a successful businessman. He was a failure with multiple bankruptcies.