I'll try to color it so you need to drag over it to read.
My take on the Ancients' Society as a whole:
While they were cognizant of the potential for chaos and destruction if they just let anyone make anything without any checks, balances, and a plan (that's good), in many ways they were also child-like, and arrogant in their ignorance and naivety. For instance, they were so certain *they* were the epitome of existence on the star, and that because *they* had never detected a soul in many creatures, it simply didn't exist. (They were later proven wrong in that by the Alexandrians, ahem.) Hermes had a compassion (in some ways) far beyond his peers, and the lack of it in his peers eventually drove him insane. Even Venat, Hythlodeus, and Hades struggled to comprehend his pain, although Venat probably came closest to understanding it, because she had experience with so much in the wider world.
In short he was told to "get over it," when he couldn't with the people the way they were.
But he, too, had some of his people's inexperience and callousness without realizing it (just like them): he created child-like beings, then sent them off to encounter whatever, *without the knowledge, experience, and adult-reasoning level, to cope with what they found.* All because he wanted proof from out there to try to *make* his society see the rights of other creatures, when the problem was right there on his own star, as were answers. He never once thought of the damage it could do *to* Meteon and her sisters (who, by the way, seemed more automatons in his eyes than true sisters, I think).
Ultimately it was the society's refusal to even consider there was anything wrong with what they did ("because we're gods") that kicked everything off, and after it all blew up with the confrontation at Kairos, only Venat and the ones she convinced to help her were willing to admit that. Those who would not, went the Zodiark route and ended up inadvertently tempering themselves. Venat realized the people needed to "grow up" by experience, and the only way to do that was to take away their god-like powers (and prevented the second "sacrifice" btw. They had to grow strong enough to resist Despair, and to *value* life despite suffering.