something that surprised me when Ordeal Call 4 released, was about how much some parts of fgo fandom refuses to engage in some themes of the story, specifically about the concequences and guilty of destroying the lostbelts, because i though most of the fandom agreed about how despite the need of chaldea to do what they did, the habitants of the lostbelt didn't deserve it.
like, it is genocide, what chaldea did IS genocide. it doesn't matter if they were not suppose to exist anymore because they were pruned, it doesn't matter if the alien world chaldeas plans were to destroy them to since the beginning. Chaldea decided to go to each of the lostbelts and destroy them for their history. It was 5 lostbelts direcly destroyed by Chaldea, the people of the 6th lostbelt could be saved, but Oberon was the one that killed them and the 7th lostbelt was destroyed by ORT.
5 different timelines is a lot of people, people that wanted to survive and exist as much as chaldea wanted, so the fact that Metatron decided to not accept what Chaldea did as just is totally valid, if anyone decided that chaldea deverve to be punished for this genocide, this is valid and they would not be wrong.
Yeah, Chaldea didn't have another option, a different possibility literally didn't exist and feeling guilty (something that everyone in chaldea feels) is valid, people thinking that chaldea should pay for committing genocide in a scale that never happened before is also valid.
Is not the story trying to gaslit you into feeling bad, is a constant theme of the lostbelts. Is a moral dilemma that the characters go through, to do such terrible thing because our history is worth fighting for, because our world, despite the problems, is worth fighting for and the characters are allowed to feel bad about it, not everyone have to accept the ultimate consequences of this fight (7 genocides, the total destruction of 7 pruned timelines that recieved another chance to exist) and by the spoilers i saw, Metatron Jeanne problem with chaldea is literally that, because for a greater good, chaldea did a genocide on a unthinkable scale and is deserving of judgment because of it (and of course the angel second only to God would have a problem with chaldea actions).