The scene could be ironic juxtaposition meant to create a sense of unease in the readers. The first propoganda scene didn't have someone acting super uneased about it either. Maybe Oda is doing the scene like it was something out of Starship Troopers.
The first propaganda scene is the kids being taught about Oden in act 2. That scene is supposed to be read as propaganda to us readers BECAUSE WE KNOW ITS A LIE… We the readers already know Orochi is a bad guy
this scene is NOT propaganda because Oda has not shown that these are bad people. Hiyori is not shown to be a bad person. the story doesn’t act like anything is wrong with her
and so the only way to tell something is wrong is to have anyone acknowledge it’s wrong
starship troopers has such things. The film begins in the class room with the teacher telling the children that violence is right and a student opposes him. Then he makes a nonsense logical fallacy to respond back to her. That scene is at the very beginning and specifically portrays the teacher making nonsense arguments for his ideology and then the rest of the movie follows his nonsense ideology
there is nothing in this Hiyori scene that is supposed to alarm us. Hiyori was not portrayed as evil or in the wrong at least and there is no one there to even slightly challenger or dislike what she’s saying
so this is simply Oda’s good wholesome ending with kids shouting for the burning of their enemies