Well obviously I'm totally with you. I feel like it's an after effect of how literature is taught in high school, where there's a "correct" interpretation (since that's easier to teach for testing purposes) and everyone is just looking for the right answer. I saw the movie twice and the second time I was consciously looking for anything that would go against the little theory in my head, and there wasn't anything which shows how wide open it is. Yes, there's how I like to think about the film, and there's how I think maybe Nolan meant the film, but I think mostly Nolan meant the film to be fairly open. Which is refreshing!