Incidentally, people say the taxi scene is evidence he doesn’t have powers. But really, it’s just NOT evidence that he does: just because he didn’t fly home, doesn’t mean he couldn’t have. More generally though, there’s a reason I presented that in such an adversarial manner.
Yes, from the literal text of the movie, it’s obviously intended to be ambiguous.
But from a film-making perspective, I don’t understand why you would make construct the movie in a manner where he doesn’t have super-powers, but the movie will lie to you and say he does. For instance, I don’t think he really summoned a giant bird-robot monster to destroy New York, because I understand the purpose of that scene in context. I can’t construct a message from this movie that I’m satisfied with if it’s all just in his imagination.
I can construct a read of the film where the fact that he has these powers, but keeps them secret, and that the act of keeping them a secret means something (if you’re trying to be an actor, it doesn’t matter if you can move things with your mind or fly. They don’t help you act or write any better.)
At the end of the day, I think unreliable narration is incredibly tricky and must be handled very, very carefully. If you’re going to unreliable-narrate to me, you need to utterly convince me that you know exactly what you’re doing. I have to believe that the author / director has constructed the work with sufficient care that when I try to unravel truth from falsehood, I’m confident that it isn’t a waste of my time. Otherwise, I can’t know where to stop and I will unravel it all the way down until I wonder why he even bothered trying to tell me the story in the first place.
All told, this movie is too sloppy for me to have that confidence, and so I am forced to take it literally.