It’s been argued that God cannot destroy the damned as the Bible predicts degrees of punishment for the lost.
(Mat 10:15) I tell you the truth, it will be more bearable for Sodom and Gomorrah on the day of judgment than for that town.
(Mat 16:27) For the Son of Man is going to come in his Father’s glory with his angels, and then he will reward each person according to what he has done.
(Luke 12:47-48 ) “That servant who knows his master’s will and does not get ready or does not do what his master wants will be beaten with many blows. 48 But the one who does not know and does things deserving punishment will be beaten with few blows. From everyone who has been given much, much will be demanded; and from the one who has been entrusted with much, much more will be asked.”
(Rev 22:12) “Behold, I am coming soon! My reward is with me, and I will give to everyone according to what he has done.”
Now, the idea of degrees of punishment is quite controversial in Christendom, but Luke 12:47-48 seems especially clear that punishment will differ depending on how willful the sins of the damned are.
I have trouble seeing one eternity of torment as much better than another. I mean, forever = forever, torment = torment. You can argue that the torment for some might be less intense, but it’s still forever! 100 blows a day versus 1 blow a day, forever in either case, is still infinite blows for both.
However, if God judges the souls of the damned and then destroys those souls, God can surely moderate the pain of extinguishment for some. And God may destroy some more quickly, more mercifully than others.
Personally, I’d be quite fine with seeing Hitler suffer much, much more and much, much longer than Gandhi. If God gave me the choice, the good man who never heard of Jesus would die and be annihilated, never regaining consciousness after death, while the truly evil man would suffer the full, awful wrath of God in conscious torment, fully aware of the lost opportunity he missed and the fate being enjoyed by the Christians he killed.
We aren’t given much detail, and it’s not profitable to speculate — much. The key is to realize that if we take the destruction of the damned literally, this destruction does not have to be equally painful for all, nor does it have to be equally brief. Indeed, we really have no idea how long it takes to destroy a soul — only that it doesn’t take forever. Hitler may burn for a very long time.
On the other hand, recall that the Parable of the Rich Man and Lazarus speaks of agony and torment for the damned, as do many of the other sayings of Jesus. I’m not arguing that the damned don’t suffer — only that their suffering will be proportional to their wickedness, as Jesus quite plainly says in Luke. And there will be many lost whose wickedness is not great at all.
We have a tough time accepting the vengeance of God. Vengeance just seems like such an unrighteous act, accompanied by such unrighteous attitudes. But God did say "Vengence is mine. I will repay." It is never right for man to take vengeance, but it is absolutely God's right to do so. What that vengeance will look like, we probably wouldn't want to know. It is enough to know that it is a dreadful thing to fall into the hands of the living God.