I agree with his assessment in his first paragraph. But I don't believe any of the Trilogy are really "gangster" movies--they're films about family, with the Mafia as defining milieu. Analogy: "Gone With the Wind" isn't a Civil War movie--it's a movie about family with the Civil War and Reconstruction as defining milieu. "Goodfellas" is a gangter movie.

I didn't see his list, but if I were making one on the top gangster films, "White Heat" would be at the top.