Mutants could be popping up in the MCU's Multiverse Saga thanks to Thanos. Disney's acquisition of 21st Century Fox in 2019 meant that Marvel Studios could start to integrate mutants into the established MCU franchise, and so far, this process has been excruciatingly slow. In the MCU's Phase 4, Kamala Khan was confirmed to be a mutant in Ms. Marvel, and Namor referred to himself as a mutant in Black Panther: Wakanda Forever. However, there have been no other clear signs of mutantkind making themselves known to the world aside from an appearance of a Professor X variant and several teases for the MCU's Wolverine.
Marvel Studios has avoided answering burning questions concerning the origins, mythos, and culture of mutants in the MCU, instead choosing to build up slowly to what is sure to be an epic reveal in the MCU's future. When Kevin Feige revealed mutants would be ing the MCU, there was speculation about how this would occur, with popular theories landing on them entering the franchise through the multiverse or perhaps being revealed to only just now emerging. However, one theory ties the increase in the MCU's mutations to one major event in the Earth's history that happened during the MCU's Infinity Saga.
Mutants Have Been In The MCU For Centuries, So SHIELD Must Know About Them
One important piece of information that Marvel Studios did confirm was that mutants have been around in the MCU for centuries rather than just now expressing their abilities. Black Panther: Wakanda Forever introduced Tenoch Huerta to the MCU as Namor, who was quickly confirmed to be a mutant. Born in the 1500s, Namor is currently the oldest known mutant in the MCU, with his mutation granting him an elongated lifespan that has allowed him to rule over his underwater nation of Talokan for centuries. This does, however, pose an even greater question as to why mutants aren't common knowledge in the MCU, despite being around for years.
One theory by Charles Xavier, a.k.a. Professor X. A deleted moment from Iron Man's post-credits scene reveals that it was originally Marvel Studios' plan to have Nick Fury know about mutants, so it's possible that this was the case throughout his MCU appearances. If the mutant population had been kept low, perhaps growing very slowly, it would have been easy to control the public consciousness and keep the existence of these evolved humans secret from the general population.
The Blip Could Have Increased MCU’s Mutant Population
If SHIELD or another covert organization had been keeping the mutant population under control for so long, then Phase 4's increase in mutations shouldn't have been possible, but the theory goes on to state that one major historical event could have seriously impacted SHIELD's ability to control the MCU's mutants. Over the course of Avengers: Infinity War and Avengers: Endgame, the Infinity Stones were used four times, sending out an epic burst of cosmic energy each time. It's possible that these bursts of energy somehow affected individuals' DNA and genetics, allowing more and more mutations to present themselves.
Thanos snapped his fingers in Infinity War to wipe out half the population of the universe and again in Endgame to destroy the Infinity Stones. After the Avengers' Time Heist, Bruce Banner, a.k.a. Smart Hulk, snapped his fingers to bring back everyone killed by Thanos, and finally Tony Stark, a.k.a. Iron Man, used the Infinity Stones to eliminate Thanos and his army. Three of these moments occurred on Earth, so it's easy to imagine that the huge amounts of energy emanating from the Stones would have affected the world's population somehow. The rise in mutants in the MCU's Phase 4 could have stemmed directly from this.
Thanos Increasing Mutants Gives People A Reason To Fear Them
One of the key aspects of Marvel Comics' mutant-centric storylines is the discrimination, hate, and fear mutants get from non-mutant humans, most prominently presenting itself in the development of the Sentinels to track, capture, and kill them. This is an important element that can't be lost when adapting mutants for the MCU, but there was some confusion about how this would happen in the live-action franchise as super-powered individuals are celebrated and adored in the MCU. However, if the rise in mutations stems from Thanos' snap, this could easily explain the amount of fear associated with mutants.
Though mutants might have been living in the background of the action for centuries, Thanos' snap could have caused a huge boom in the Earth's mutant population. Tying the MCU's mutants' origins to a catastrophic event and a terrifying supervillain would give regular humans an understandable, if still misguided, reason to fear mutants. Adding to this would be the fact that mutations can appear in anyone, which poses the question of who can be trusted and who might be incredibly dangerous. In this way, Thanos can continue to have a huge effect on the landscape of the MCU, as it seems the fear he cultivated will never really disappear.
