This show is actually reminding me a lot of both Shinsekai Yori and Qualidea Code. Remember in Qualidea Code where the "monsters" the "humans" were fighting turned out to be humans the entire time while the humans were just monsters under disguise? Yeah. Papa and his lackeys might not even be human. Perhaps aliens, the real klaxosaurs or maybe even robots. Fuck if I know but I'm sure "humanity" as the 13 kids know it isn't the actual humanity and it's more akin to a caged humanity ruled over by whatever those masked 'Papa' things are.
In fact, I suspect Grand Crevasse to be some sort of colony for actual humans. One of their last holdouts against Papa and his race. The Parasites are the unknowing weapons used to wipe out their own race. I see Klaxosaurs as a biomechanical armor of sorts used by the actual humans to defend against Papa and this battle IS indeed a turning point for humanity. It's taken a turn for the worse instead of the better. Papa and his race are one step closer to genociding humanity. That's the Qualidea vibes it gave me.
As for Shinsekai Yori, the whole dystopian society with the "undesirable" kids being purged is very reminiscent of Shinsekai Yori and how the embryo that came out of the klaxosaur this episode was distinctly human. It reminds me of the whole humans turning into monsters thing from Shinsekai Yori. Also a very unsettling hint of what happened to Naomi. The klaxosaur from the first episode? I have a feeling the Parasites' first victory was against their own friend. Shit on this show all you want but the worldbuilding is certainly very intriguing now even if it's not exactly original.