pukunui
Legend
He is supposed to be dead, yes. But whatever he is, I think he is still real. Real enough that the others can see him. Real enough that, as @Rune says, he can do things independently of Wanda. Real enough that she has to rewind/rewrite his memory to keep him from discovering the truth of their situation.This is post-Endgame, so Vision is dead. He is not real, or at least not yet, if some of the theories are to be believed.