Kaisy and I were discussing this today.
Basically, if the villain is irredeemable, has done truly evil acts, and acts and thinks in a sophisticated manner, they probably deserve to die.
Example: if they have some kind of master plan that involves the genocide of an indigenous tribe in order to steal their resources. That mastermind should die.
If he’s a soldier in the mastermind’s army who is a dupe and “just following orders” maybe not.
But it is a complex issue, because you might like your villain so much that you don’t want them to die.
So then there is this argument: do you keep them alive in order to have them make another appearance? Or do you kill them off in order to do the story justice.
If you bring them back is that a cheap gimmick? Does that cheapen the villain’s value? Or is there something to keeping that villain around?
What to do?