This is one of those things I always wonder about, I know the characters of overlord so I get not liking them but I never really got the point in trying to punish them/wanting to see them punished outside basic catharsis. The way they're written they literally can't learn anything from being punished in the way you and many others desire because they fundamentally know of entities far stronger then them in universe. And even the fact there were humans stronger then them.
Theres no getting through to them/making them see the errors of their ways because they don't have a fundamental misunderstanding of the world. They understand it rather well it just doesn't interact with their reverence for the supreme beings or their backstories. At one-point narberal is directly confronted with a question about what if ainz was weak/human and she simply says she'd serve him regardless.
We see this even further with aura, mare, and aurola omega, all three are humanoids and receive zero mistreatment or disrespect despite some members of the tomb being written to despise humans. Because in the minds of the npcs being created by the supreme beings instantly supersedes essentially any other prejudice they're designed with. Similarly, when humans are part of ainz kingdom they're instantly considered more valuable and worthy of more respect.
They're not logical beings that have miscalculated/misunderstood anything, they're weird magical entities with preprogrammed mental states and biases that will disregard any logic in face of those biases. Demiurge isn't evil because he's sick in the head or has a traumatic backstory, he's evil because his god wrote that he was evil. Similarly, narberal doesn't really hate humans for any reason beyond a note in her backstory "Humans are disgusting"
I guess to me punishing them always felt rather purposeless you can't get through to them or show them the errors in their ways because they haven't made errors. They're just categorically insane and self-contradictory by any real-world metric (Im honestly of the opinion if you asked a therapist to talk to them the therapist would give up with a note "not human enough to deal with"). Demiurges only thought if he was tortured/killed is how he wishes he'd been smarter/prepared better and how sorry he is not to have served his master better. Because to him the flaw isn't what he did but that he wasn't prepared enough/ready enough to deal with whatever problem stopped him in his tracks.
