Doctor Strange in the Multiverse of Madness was originally set to be released on May 7, 2021, but the COVID-19 pandemic pushed Marvel Studios' entire Phase 4 slate further down the calendar. After initially shifting to November 5, 2021, the sequel ultimately landed a 2022 release date (which recently changed again from March 25, 2022 to May 6, 2022).
Spider-Man: No Way Home was supposed to be released after the Doctor Strange follow-up, but with Sony Pictures intent on having a new movie starring the wall-crawler swing into theaters every two years, that changed. As you might expect, it had a significant impact on the MCU timeline.
In the midst of writing the screenplay, writers Chris McKenna and Erik Sommers learned of the schedule change caused by the pandemic and got to work on making some significant alterations.
"We were actually working off of things that were happening in 'Doctor Strange 2,' and trying to incorporate them into our script," McKenna tells Variety. "When we started writing, [Strange] knows firsthand the dangers of screwing with these things. Then we changed it so he was a person who doesn’t know that much about the Multiverse."
"But that makes it even more frightening, to start fooling around with these things, because it’s the fear of the unknown," the writer said of how the change improved Spider-Man: No Way Home. "Either way, he was the voice of reason going, 'You don’t mess with the fate of an individual' - and Peter Parker being naive enough to go, 'Why not? Why can’t we save these people?'"
This suggests that our exploration of the Multiverse won't end with Doctor Strange's next solo outing as Marvel Studios clearly plans to address the fallout from that movie in future stories. It's interesting to wonder how different Spider-Man's latest adventure might have been had Strange already crossed paths with the Scarlet Witch, but No Way Home now serves as a prologue of sorts to the upcoming sequel.
You have to believe these release date shifts changed Doctor Strange in the Multiverse of Madness as well, because the first trailer for the movie strongly indicated that Strange will have to deal with the fallout of the spell he cast to make the world forget that Peter Parker is Spider-Man.