hot take but we as a society need to be more comfortable about discussing "icky" parts of history, and even telling the side of the "bad guys"
history is written by the victors, and will be heavily biased. The defeated will be painted as evil, deviants and/or like they have always been "the bad guys".
Reducing people to "the bad guys" does a huge disservice to the opportunity of learning from the past, because it creates a distance between the modern reader and the actual events, it creates the comfortable position of "I'm not like the bad guys, so i will never make their mistakes"
I think is important we understand how and why people believed in something, and where did things turn a certain way. Yes. Even "the wrong side". Even the nazis. Even those people you are thinking about, whoever they are.
Because you are not immune to propaganda and it's so so so so important to understand what happened and how did we get to those points before we fall to the same techniques again and again.
"Learning from the past" isn't deleting the ugly parts or cringing when someone brings up war. Thinking otherwise is a huge mistake and precisely what someone who wants to make the same mistakes wants you to think.