Sam Raimi confirms that John Krasinski’s Doctor Strange cameo was nothing but fan service
Don't count on that version of that character ever appearing again
About halfway through Sam Raimi’s Doctor Strange In The Multiverse Of Madness, the eponymous wizard finds himself lost in the eponymous multiverse, with him and new buddy America Chavez finding themselves in an alternate reality where their Doctor Strange is dead and their preeminent superhero team is not the Avengers but the Illuminati—consisting of a bunch of fan-favorite cameos from beloved superheroes and actors, as well as Black Bolt of the Inhumans. One of those cameos in particular, John Krasinski as Reed Richards of the Fantastic Four, was a payoff to years of fan-casting, based largely on the fact that Krasinski looks a fair amount like the character and that it would be fun to imagine him as Mr. Fantastic and Emily Blunt as Sue Storm.
This version of Reed Richards meets a grisly death at the hands of Elizabeth Olsen (who never met him while filming, apparently), so he’s definitely not coming back (unless someone is serving up a nice plate of Mr. Fantastic spaghetti), but anyone hoping that Krasinski’s casting is a tease for future Marvel adventures from the former Office star should start looking for a way to get into another universe… because it’s not happening in this one.
As reported by Comic Book Resources, the commentary track for Multiverse Of Madness features a moment where Raimi notes that Krasinski playing Reed Richards was a decision made by Marvel Studios boss Kevin Feige and that it was specifically done because “fans had a dream of who the perfect Reed Richards would be”—meaning Krasinski was chosen just for that reason and not for anything he brought to the role as an actor, which may be a real shock to anyone who saw his incredibly magnetic performance in the film.
Raimi also specifically says that Feige wanted “that dream” to come true in this “alternate universe,” which seems to imply that the canonical main universe version of Reed Richards will not end up being John Krasinski. That seems obvious in retrospect, since Marvel wouldn’t have blown the big moment of revealing the MCU’s Mr. Fantastic in a one-off cameo, but it’s also indicative of Marvel’s goal of making its eventual Fantastic Four movie a certified Big Deal and not yet another failed big screen adaptation for the iconic super-family. We know Marvel Studios is looking for a big name to replace Spider-Man trilogy director Jon Watts, and that big name won’t necessarily want to be stuck with John Krasinski’s Mr. Fantastic.
So it seems like the awful pile of stretchy strings is the last we’ll see of that version of him.