Voldemort doesn’t want the world destroyed, and he just made Harry into a world-destruction-preventer. Pointing this out — and pointing out that Harry is now a better world-destruction-preventer than Voldemort could become — doesn’t involve changing Voldemort’s utility function.
(Voldemort can’t swear an Unbreakable Vow akin to Harry’s because nobody has trust in him that could be sacrificed to power it.)
He didn’t make Harry into a world-destruction-preventer. He only made Harry swear not to actively destroy the world. Also, while Merlin might think that with all the effort Voldemort went through to prevent Harry from destroying the world it would be easier to destroy the world with a piece of cheese, I wouldn’t find that so comforting.
Voldemort doesn’t want the world destroyed, and he just made Harry into a world-destruction-preventer. Pointing this out — and pointing out that Harry is now a better world-destruction-preventer than Voldemort could become — doesn’t involve changing Voldemort’s utility function.
(Voldemort can’t swear an Unbreakable Vow akin to Harry’s because nobody has trust in him that could be sacrificed to power it.)
He didn’t make Harry into a world-destruction-preventer. He only made Harry swear not to actively destroy the world. Also, while Merlin might think that with all the effort Voldemort went through to prevent Harry from destroying the world it would be easier to destroy the world with a piece of cheese, I wouldn’t find that so comforting.