I don't believe it's very useful to categorize people or things as evil if they don't themselves think this is their motive.

The "evil" category often makes people think that the "evil" entities have some motives and logic of operation that "good" people just can't understand or relate to at all.

There was a sort of internally coherent logic and motivation for Nazi death camps (and to many similar horrors). I don't agree with it at all and I find the results of it extremely harmful and such logic must be vigorously resisted. And to vigorously resist it, it has to be understood.

However, I'm not at all sure that I would have resisted the death camps if I were to formulate my views in the same situation as Nazi germans were. I could well be a Putinist in current Russia. And I probably wouldn't think I was evil.