Given that Charlie Coxs work as Matt Murdock on Daredevil: Born Again, as well as Robert Pattinsons turn as Bruce Wayne in The Batman, it might be easy to understand why Ben Affleck recently announced that hes done with the superhero genre. Afflecks two outings in the world of tights and capes, in 2003s Daredevil and later the Zack Snyder 2010s era of the DC Universe, were largely met with critical and audience division.Anyone just focusing on Daredevil or Batman v. Superman: Dawn of Justice might therefore think that Afflecks retirement from superheroes is no great loss. Thats especially true in light of Afflecks undeniably great performances outside the genre, such as the insincere, possible wife-killer in Gone Girl or as an alcoholic basketball coach in The Way Back. Affleck excels at playing bone deep exhaustion and is able to retain an innate likability and humor even when hes trying hard to be indifferent.Granted, those skills dont immediately lend themselves to superhero stories, with their emphasis on power and victory. However, there are several roles about a hero in retirement, his best days behind him, that would have benefitted immensely from what Affleck brings to the screen. One might point out that Affleck came near it, too, in the Snyderverse, which drew heavily from The Dark Knight Returns and Kingdom Come. But both of those are, ultimately, about Batman dragging his battered body back into the fight, and always coming out victorious. He is a traditional hero once again.No, the better Affleck Batman role would ask him to stay out of the fight, to grouch from the sidelines while still charming audiences. The superhero role he might have always been meant to play was as Bruce Wayne in Batman Beyond.A spin-off of the beloved Batman: The Animated Series, Batman Beyond takes place 40 years in the future. An aged Bruce Wayne has long since retired, a victim of his outdated methods and deteriorating health. However, he happens to meet a teenager named Terry McGinnis, who learns about Bruces secret cave. After his father is murdered, Terry steals the Batsuit and pursues his own sense of justice. Seeing himself in Terry, Bruce agrees to train and support the kid as the next Batman.Batman Beyond ran for 52 episodes across three seasons and has continued in various animated movies and comic books, achieving its own cult status. It is exactly the type of story that would fit in James Gunns vision of the DC Universe, one in which fan favorites such as Creature Commandos and Booster Gold get attention. And its exactly the type of caped role that Affleck should have played.By this point, grouchy and secluded versions of Bruce Wayne are common to the big screen. Christian Bales Bruce began The Dark Knight Rises as a recluse, having apparently hidden in his house for seven years. In The Batman, Pattinsons Wayne shuns the spotlight, ignoring even his companys business. And Affleck himself portrayed Bruce Wayne as a man who had temporarily given up his masked identity, only returning when Superman arrived on the scene.The Bruce Wayne of Batman Beyond is totally different though. This Bruce Wayne has been retired for 20 years. Alfred is long since dead. Robin was kidnapped and tortured beyond recognition by the Joker. His only acquaintance is Barbara Gordon, the one-time Batgirl and current police commissioner who has left him in the past, embittered. Hes completely alone and not used to being around people until a man very much like himself arrives.This type of Bruce Wayne would have given Affleck room to be completely unpleasant and an irredeemable grouch to an almost laughable degree. But it also would have called on him to show surprising warmth, to win over the audience, even if he doesnt seem to want us on his side. Affleck could play the older Bruce as the same big and abrasive supporting personality he portrayed in Air and The Last Duel. And as he did in those movies, he would still charm us with his infectious personality.Of course were saying all of this right when Afflecks saying again today that hes done with superheroes. And of course theres no Batman Beyond movie currently on the books. But given that Affleck is currently 52, the same age as Bruce at the time of his retirement (and a very important number for DC), theres still plenty of time for him to change his mind and decide to return to the world of superheroes again the grouchier the better.