@LukeAlmighty @dave it's the next guy's problem infinitely, which means nobody ever has to die, which also means that more and more humans will have to be created just to be strapped to the rails, which means that (until the god's power is exhausted, that's foolishly offering this test) humanity is WINNING the galactic out-populate-them contest that's going on right now that nobody's told you about.
The danger is that after building up to quadrillions of potential victims, that you hit an evil enough or stupid enough person that they kill people unnecessarily, and humanity is immediately extinct instead. Which is why the lever's most likely to pulled at small numbers, as people realize what shaky ground they're relying on and prefer small numbers of dead, then maybe less likely as the numbers become oppressively large (I'm REALLY SURE that some asshole's going to pull the lever at a worse stage, but a billion people... I just can't), and then inevitably the lever will be pulled.
Which means this test can really be summarized as:
>Does anyone in your species have mental illness?
>If it does and you're insufficiently cautious of that, your entire species will be annihilated.
Which is a way of allowing two kinds of adults onto the galactic scene: angels, and non-angels who can be expected to apply some group restraint.