Why should anyone care what van Norden has to say on the subject anymore than anyone else? Anyone who adopts an idea to paint themselves an “authority” on it shouldn’t be trusted, especially in this domain.
van Norden is an award-winning scholar who has dedicated his entire life to classical Chinese philosophy. He has taught the subject at universities for decades. I think his PhD earns him the privilege of being seen as more of an authority on this particular subject than Benjamin Hoff, whose credentials are a BA in Asian art and learning a Japanese version of Qigong as a hobby.