Hitler is in fact two things, he's some rando that was propped up by the Americans to sack Europe so that they could have their hegemony, and he's also The Great Satan in The Church of Boomer.

To the Boomer, 1000 Stalins and 1000 Pol Pots can never compare, because Hitler is infinitely evil, and you cannot meaningfully compare anything else with infinity.

Hitler Appreciators are kind of like The Church of Satan. They have no belief system of their own, they just adopted The Church of Boomer, but inverted. If you tell them that Hitler is a terrible choice of hero, they'll accuse you of paying undeserved respect to The Church of Boomer - which you can never really prove you're not.

The short of it is, The Establishment is aware of reverse psychology. They know that if they vilify someone, those who dislike them may read that person's work. So the great anti-establishment heroes will never show up in their history books, favorably or otherwise.