@Kampfarsch The whole point of KnY is to continue living, in despite of all things. That's why the author tries to give attention to their villains' backstories and show that they were just normal people at some point, but because of their miseries they choose the easy way to live, to be strong and immortal as a demon. But just like you said, that doesn't redeem them at all, and that's why the heroes don't hesitate to deliver their judgement. Even though they lived through miseries, they're still monsters that need to be destroyed. But if that's true, the opposite is too. Why should I have compassion for some monster whose only purpose is to hurt and kill? "Because they were people just like me". Tanjirou literally resumed the whole message Gotouge is trying to pass, which happens to also be his own way of thinking. But even when Tanjirou shows his compassion he doesn't hesitate to destroy evil; which is, in some way, also a form of compassion that, by killing his enemy, they can't do more evil. Tbh you didn't understand or simply don't want to.
And chill, nobody is trying to fight here. lol