Compare: in principle, it would be a good thing to farm short-lived happy humans (perhaps for their organs) who would otherwise not get to exist at all. But we find the idea repugnant, and that’s probably also a good thing. It causes us to lose out on some life-saving organs, and the value of the farmed lives themselves; but it may also prevent us from committing worse atrocities against each other.
This part reminded me of The Promised Neverland.