The problem tends to be that (1) experts are only experts in their own fields, but have a distressing tendency to think that makes them experts in all fields and (2) an expert is often only an expert if unchallenged. Plenty of ‘experts’ have had their research get supplanted—or attempts have been made to supplant it—with newer, more accurate research, but the older so-called experts often fight against that newer research so as not to lose their exalted status. Sadly, you see often in science (look at how Louis Pasteur was treated when he dared to suggest bacteria caused disease).