Some of those were done so the film could have “more fun with the multiverse” - Loki creator Michael Waldron is the writer - by adding cameos and variants of existing characters. Doctor Strange in the Multiverse of Madness was beset with production troubles related to COVID-19 and underwent “significant” reshoots as late as March this year. It hasn’t been smooth sailing for the making of the movie either. (You could also argue that Loki and Sylvie are equally to blame, given their actions on Loki.) But the highs are now being contrasted by his lows, with his dimension-shattering spell in No Way Home breaking open the multiverse, creating ripple effects that will inform the new Doctor Strange movie. Though to be fair, Doctor Strange had an important role on the mega get-together Avengers: Infinity War, before helping reunite everyone for the big battle on Avengers: Endgame. After a brief but pivotal presence in Spider-Man: No Way Home, Benedict Cumberbatch’s wizard takes centre stage in the Marvel Cinematic Universe with Doctor Strange in the Multiverse of Madness, six years on from his last solo adventure.
Doctor Strange is back - in a movie of his own.