Marvel Studios' Avengers: Doomsday | Official Trailer

Robert Downey Jr.'s recent comments about his role as Doom in Avengers: Doomsday can be argued to have debunked a common MCU theory, though this may not be true. Arguably the biggest movie reveal at San Diego Comic-Con 2024 concerning the MCU centered around Downey Jr.'s return to the franchise. While his return does not come as Tony Stark as many have theorized since the Multiverse Saga began, RDJ's return as the titular villain in the story of Avengers: Doomsday became quite the talking point.

Since this announcement, the upcoming Marvel movie has been the subject of many a theory, with several exploring the potential connections between Doom and Tony Stark. With an actor as iconic as Downey Jr. coming back to the universe that catapulted him into stardom, this was to be expected. However, Downey Jr.'s comments about the version of Doom that will appear in Avengers: Doomsday led many to believe their theories had been quashed, but the opposite could be true by the time of the film's May 2026 release date.