Indeed, for the lucky someone whose first film viewing experience is OUATITW, Frank is simply a character.
I will admit your post made me chuckle - I agree with you on the Bronson avatar.
For example me. (OUATITW wasn't my first film, of course, but first and still last with Fonda.) And, believe me, his acting is more important than his previous roles. I was shocked by his coldness, no matter what his usual roles were.
I wonder if that's going to be the discredited 2005 cut of the film?
(also with this version the audio is still in it's unsweetended state. Just to warn you)