> Except that your mind is not an isolatable computation

This doesn't follow from what you write next. You are saying that the computation needed to generate a mind is very large. I agree that it might be the case, and I would say that nobody knows how large. Do you really need to simulate in minute detail what is going on in every distant galaxy? Seems doubtful, but who knows?

All I'm saying is that if this computation is finite, and the universe-in-the-large-sense (entire timeline, branches if you accept the Many World Interpretation, and so on) is infinite, then infinity wins.