A long time ago, on a social media app far, far away, a fan of the Marvel Cinematic Universe made a photoshopped image of John Krasinski in a Fantastic Four suit. This started the campaign to actually cast Krasinski as Reed Richards in whatever film Marvel may actually put him in, which they actually did for a short sequence in Dr. Strange in the Multiverse of Madness, to a great many oos and ahhs from the crowd.
This is a process called “fancasting,” in which fans of a thing dream up the best possible actors, directors, or players to actually create and execute said thing.