What if homo sapiens died out and the Neanderthals who succeeded decided to simulate how history would have gone if it were the other way around, effectively resurrecting the extinct humans, additionally adding in ethical considerations such that everyone born into the simulation would have an unending post-life existence optimally fitted relative to their own preferences?

Just because we only see part of the picture doesn’t mean the whole is as unethical as the part we can see seems to be.