Personally, it would be when people say that history is written by the victor ,I tend to really hate that quote because it’s often being use in a way to somewhat defend the nazi (and has been proven false considering how much myth the german general perpetrated after the war such has "hitler delayed the me 262/him being blame for every single military mistake as if the general did nothing wrong) ,also when the ally are made to be somehow as bad as the nazi ,i think doing this diminish the scale and the gravity of the nazi crime and I often see the “both sides” trope being use to try to excuse the nazi crime (I think it’s possible to have honest discution on ally atrocity ,but please don’t use them to excuse the nazi one ,it’s bad)
I believe it is historically a true statement more so when pre-modernity if you defeated the enemy you completely destroyed your opponent and enslaved the rest, making it difficult at best to get any opinion of the enemy, a good example might be Kadesh, where even in modern times we wholeheartedly believed in the Egyptian narrative because that was the only view we had to reference, until we dug up the Kadesh peace treaty in Anatolia, only then discovering the other sides viewpoint and allowing us to open the discussion to any other possible outcome. But with the benefit of modern mediums we have records often of the views from an enemy. Propaganda my friend, that’s all it ever is and with individuals understanding a much larger world at play the narrative is bound to have to change with the dissemination of information. Thanks