From commenter Imag:
If Hitler had been able to compare stuff to Hitler, he totally would have done so.
Right; to the extent that invocation of Hitler has become insipid shorthand for having nothing useful to say while demanding extreme measures, Adolf Hitler himself would have used his own example extensively. Leni Riefenstahl would have prominently featured him in Triumph of the Will, in a manner not unlike the way that Norm Podhoretz uses him today. Hitler is a convenient excuse for whatever policy you want to pursue, irrespective of what that policy may be; the original Hitler would undoubtedly have depicted Sławoj-Składkowski, Daladier, Chamberlain, Churchill, Roosevelt, and Stalin as Hitlers, bent on world domination.