The original hero in the Marvel Cinematic Universe wasn't Iron Man, but rather the World War II icon Steve Rogers aka Captain America. Rogers' adventures came to an end with the conclusion of Avengers: Endgame, and he's since been succeeded by Sam Wilson, who was previously his former sidekick, Falcon. Some fans, however, felt that another former ally of Steve Rogers might have made more sense as the new Captain America. That's especially the case given the current state of the Marvel Cinematic Universe.
Source：https://www.cbr.com/captain-america-bucky-barnes-succeed-steve-rogers-mcu/
