Subjective is right. Fair point on supporting role but I think it's tricky. In the De Niro circle they'd tell John Cazale heads and shoulders above was the best.
I like Matt Damon but he's always Matt Damon playing a version of Matt Damon. My favorite role he's done is Stuck on You. I think his costar in Rounders, Edward Norton, is a level above. He can really sell a character. He literally scared me in the flashback scenes in American History X
Are you serious? Bill the Butcher is one of the most iconic characters in cinema history. Way more iconic than any character Oldman has played. DDL also has Lincoln and many consider his role at Daniel Plainview the best acting job in cinema history
Scientific Fact: Porta Johns are like Aspens trees. One large organism. All interconnected. PS, lay off the breakfast burritos at Speedway. You've developed quite the reputation.