On the point of Hydaelyn -
Her entire reason for being, her raison d'etre, is protecting the races of man from being sacrificed to Zodiark to resurrect the sacrificed Ascians. She literally exists for that one reason. Hydaelyn does not exist to determine or dictate humanity's future; she exists to make sure humanity has a future and, far as I can tell, is hands-off letting people do their own thing and only intervenes when her prime directive necessitates it.
Given she was created using the same Ascian creation magicks that create primals, has anyone considered she was created with imperfect knowledge of the situation? Primals are whatever their summoners want them to be, and if her creators didn't include that information, she wouldn't know it...
Regardless, even if Hydaelyn deliberately and knowingly lied about her conflict with Zodiark, that doesn't change the fact the Ascians have every intention of destroying all the shards via Rejoining and then sacrificing the entirety of mortal life to Zodiark to resurrect the dead Amaroutians. We'd need to oppose the Ascians anyway, and as Hydaelyn hasn't shown any sort of ill will toward the Warrior of Light or mortals in general, I don't see what the issue is.
Hydaelyn's entire reason for being is protecting the races of man from becoming fuel for Zodiark's resurrection of the dead Ancients. I don't understand why people are so insistent on pushing some kind of narrative that paints her as evil or malign.
(For the record Zodiark doesn't sound like he's evil either - just a wish machine created by the Ascians, for lack of a better term, but he still requires equivalent exchange. It's the Ascians' inability to let go of their glorious, dead civilization that's the issue at the end of the day.