If Satoshi were not dead (or, alternately, if Satoshi was not a front for the CIA/NSA/etc.), then they obviously they would have revealed themselves 10+ years ago.
I don't think that's the best line of thought. Of course, it might be the most likely one. If Satoshi was not a three-letter agency, he doesn't necessarily need to be dead.
The maximum supply of 21 million might be related to the blocks, but what if he actually wanted it to be 20 million? Would that be too foolish? Instead of building an entirely different use case, one could simply stick with the original idea and implement a supply control of 1 million, effectively "burning" the excess.
If that's not the case, a suicide is highly probable in the event of losing the keys, for instance.