My sole thought at the end of Pandaemonium was "Am I supposed to feel good about any of this?".

I already had a bad feeling once the first tier was confirmed to be in the past, and while the story was interesting, I had a nagging hunch there was no way anyone was getting a happy ending, but hoped I'd at least be able to end it with a clean conscience by telling the truth to Themis and company instead of just acting to maintain history's twisted course; especially because the law of causality dictates that we literally can't change the future and fate would either conspire to keep things the same, or we'd spawn an alternate universe while our own timeline remains unchanged.

Themis opts for willful ignorance so he could continue to feel good about us despite having even more reason to hate us after knowing of our involvement in the past and Ericthonios consigns himself to a lonely solitude in Pandaemonium until the day he died in the Sundering out of duty to his people and no amount of praise and comforting words from them is going to keep me feeling like my WoL was a terrible person for not telling them anything to try to spare them from cruel fate.