Interestingly (at least, I think it's interesting), I'd always felt that way about time, before I learned about quantum mechanics. That's what a four-dimensional spacetime means, isn't it? And so science fiction stories that involve, say, changing the past have never made any sense to me. You can't change the past; it is. And no one can come from the future to change now, because the future is as well. Although now that I think about it more, I realize how this makes slightly more sense in this version of many-worlds than it does in a collapse theory.