Holliday seems to be a self-proclaimed expert, and everyone in the industry sort of went along with it. He was definitely well-liked and does know his stuff, but according to a very surprising discussion on another forum a few years ago, he owes his success to a lot of people who helped him with his research and books who he quickly tossed aside once he was done with him.
My issue with Holliday is that he calls other writers and historians "idiots", "pinheads", etc. if they get some facts wrong. Yet he gets the years wrong on several of the films in his books, as well as a few cast misidentifications and omissions. He also claims that his book is the undisputed record for the best of the period, but there is definitely room for revision and/or improvement.

