I’m going to go with the conspiracy theorists. New England over Denver, because Brady is the better representative of the Old School NFL. Carolina over Arizona, because Cam Newton is a better representative of the New School NFL.
Then New School NFL over Old School NFL for the 50th Anniversary Super Bowl, thereby symbolically denoting the transformation of America into the New America. Predictive programming calls for Carolina.
One could, of course, reach the same conclusion simply by comparing teams, but it’s more fun to prognosticate The Game of Pigskins via the NFL Narrative.