Here’s the rally at the end of the second movie where he shows those visions
Grindelwald is the Hitler analog who is trying to enslave humanity. But he’s the one trying to prevent the Holocaust. It’s insane.
Im going to guess that in the third one he goes too far in an uncharacteristic manner like what happens to a lot of these villains because even if he is ruthless there has to be some extra shit to convince the audience that the guy preventing the deadliest war in human history is the true villain. Even if he is using that for propaganda purposes and is megalomaniac… I mean shit… Its world war 2
I found a YouTube link in your comment. Here are links to the same video on alternative frontends that protect your privacy: