That's apples to oranges. A physician goes through a rigorous training and licensing process before they can practice medicine. There's a base level of proficiency and ongoing continuing education requirements to be a physician. There is no such process for the nebulous and ill-defined field of "public policy" which could be stretched to cover just about any facet of daily life.

I therefore can only judge a self-proclaimed public policy expert based on what I can find about them. My cursory google search revealed no interesting papers written or talks given. Only a bunch of short, shallow blog posts.