Serious question. What have I been falsely indoctrinated about? What should I have been exposed to as an alternate view on nazis? Do history books count as "indoctrination"?
To your other point, I would imagine showing aliens concentration camps would make them recoil in horror, yes.
The issue is not whether Nazis were/are bad. You can feel safe in the assumption that all but an extreme fringe minority are in consensus that Nazi philosophies and practices were horrific beyond comprehension.
What we should contemplate and discuss, however, is what were the economic and cultural conditions that led to the rise of Nazism in Europe in the 30s, and how it came to be accepted, supported and enabled/served by such a large proportion of the population.
Only by fully understanding these issues can we take effective measures to ensure such a movement never takes hold ever again, and ensure that we as individuals are equipped with the strength and judgement to avoid succumbing to populist bigotry any time we see it.
But, IMO, morality and ethics are subjective, so for a minority of people who don't share this consensus, yes, nazis aren't bad.
An alien race that has constructed a feudal slave society might not object to concentration camps at all. They might love the idea.
Nazis, from a purely objective standpoint, are not bad. But not good either. What they did is facts.
Only when the human observer comes in, ie, you and me, we introduce morality and you and me both think that those things are bad and should not be done.
Or how Death expressed it in Discworld; "take the universe and grind it down to the finest powder and sieve it through the finest sieve and then show me one atom of justice, one molecule of mercy"
Would an amended statement make more sense?
“The nazis were bad to the degree that badness is a thing.”
Although it seems a bit silly to phrase things that way.
To the degree that silliness is a thing of course.
Personally I believe that my notion of bad, good, evil and angels is purely subjective. Doesn't mean they have less value. I merely acknowledge the value is subjective. Like how a childhood toy holds sentimental value.