People have played and watched sports since the dawn of time, and there is no reason why that should change in the future. There is an ancient idea of Bread and Circuses that applies just as easily to the future, too. The phrase means to generate public approval, not by excellence in public service or public policy, but by satisfying the most immediate or base requirements of a populace: for example food (bread) or entertainment (circuses).
Superman is a sci-fi character. He’s from another planet, after all, and Batman, from a certain point of view, is a sci-fi character, too. Batman is a super genius with the money and resources to develop incredible technology. He has traveled through time, to other planets, and spends a good deal of his time aboard a space station. But somehow this isn’t enough in my mind to make either of them real sci-fi superheroes.