There is one detail in Avengers: Finale that suggests that Kang may have been afraid of Iron Man (Robert Downey Jr.). The shadow of Kang the Conqueror (Jonathan Majors) looms over the future of the Marvel Cinematic Universe, and he has been confirmed as the linchpin holding the Multiverse saga together. By the end of Phase 6, the impact of his arrival will be revealed, and in Ant-Man and the Wasp: Quantum Theory, season 2 of Loki, and Avengers: Kang Dynasty, he’s almost certainly wreaking havoc on the MCU’s hero roster. and villains. However, Tony Stark/Iron Man is the only character that Kang most likely won’t have to fight anymore, and he may be very happy about it.
In many ways, Kang seems to be responsible for most of what happens in the main MCU timeline, to the point that he seems to be responsible for the route that some characters have taken through the story to the present. “I paved the way… you just followed it,” he said after clashing with Loki and Sylvia in season 1 of Loki, episode 6 of For All Time. Always.” That would mean that Kang—or at least the first iteration to appear on screen so far, “The One Who Stays”—most likely knew about Iron Man’s journey, his actions in the MCU, and his sacrifice at the end of Avengers: Finale.
Tony Stark seemed to be the only Avenger who knew about the consequences of messing with time travel. In “Avengers: The Finale,” he said: “You connect with time, it tends to come back.” While it’s unclear what he’s talking about, it at least indicates that Stark had some experience with the dangers of time travel. Not only is Iron Man a formidable opponent, spilling Thanos’ blood and eventually defeating him with the biggest sacrifice made in the MCU to date. He also seems to be the only Avenger with the foresight, knowledge, and time travel experience to take on Kang. It was for this reason that Kang may have been afraid of Iron Man, potentially even paving the way that eliminated him from the equation.
Why Kang might be afraid of Stark
Time is Kang’s domain. He is a time-traveling, multi-variant supervillain, and the only iteration that viewers have met so far has managed to control the flow of time and space, taming the universe into one thread. The evil version that is likely to appear in the future of the MCU will be the genius Nathaniel Richards, Kang the Conqueror, who is again portrayed by Majors. In the comics, Kang used his “time ship” to travel through time, collecting technology and using it to prove that he is more than just an academic, repeatedly fighting the Avengers and other characters along the way. The only person he won’t want to argue with is someone who has an understanding of time. And Tony Stark not only mentioned the dangers of messing with it, but also played an important role in creating the time machine that was eventually used to defeat Thanos.
In the comics, Richards doesn’t have superpowers per se, he’s just a genius who uses his knowledge of time travel to transform into one of Marvel’s greatest supervillains. His most dangerous opponent has to be someone equally smart, and Stark meets all the requirements. Using his foresight of the dangers of time travel, and once Kang’s threat is fully realized, Stark will undoubtedly come up with a plan to defeat Kang. No wonder then that Iron Man was the only Avenger Kang was afraid of. Perhaps, then, it’s a pity that Iron Man no longer exists (at least not in the main MCU timeline) thanks to the events of Avengers: Finale.