Is authenticity externally determined, or internally determined? Is there an external objective or universal standard of authenticity, or is it more of an internal integrity or trueness to one's self-determined values? Or a blend of both?
If it is internally determined, then an objective measure cannot be known to exist. That's the contention I have with the author's thesis, as the author is assuming external/objective authenticity. As an example, consider Hannibal Lecter: Certainly authentic to his self-determined values, yet not compatible with the author's view of authenticity, and would be considered a "bad person" by the rest of humanity.