Marvel already tried to tackle the registration act not with mutants but with superheroes in Civil War and I was left very unimpressed with the undercooked story . The famous airport scene in civil war that was meant to show why many of them were on different sides became a party and more about Spiderman making his first appearance in the MCU than the registration act itself. The story never came to any fruition after that. it was quickly switched into another undercooked story of Bucky killing tony's father.