Well, now the Warrior of light is a Genocider of Alexanderia, we killed creatures who could "Think, hear and feel".
the WoL's excuse? they had no aether so they weren't real, is that valid? maybe we should ask Emet-Selch he said

"To live in ignorance is a form of bliss, is it not? Just as it is for the likes of you. The powerless, the feeble, the weak... None of you belong here. My world is one of high magic. A place where lives burn brighter than a thousand suns... Not that any of you would comprehend such a thing. Your souls are fragmented, your aether thin and weak. You are broken. Ineffective, useless, an affront to my very existence."


I'd also like to direct you to a Topic made by Dave Fishnomer touching this exact issue.
https://forum.square-enix.com/ffxiv/...poilers-inside