What's the point with that quite lackluster story in Endwalker?

[Rulakir]

The most boring thing they could've done would be to make Zodiark or Hydaelyn the big bad, which they didn't.

Except Hydaelyn is still the antagonist to the Ancients, even moreso now given what we learned in EW. I didn't clarify this enough in my initial response as to why I felt like the narrative was gaslighting me. Her actions align more with the villains, in fact she shares numerous similarities to Hermes, but the storyline treats her as the opposite. Even saying she's the heroine of the WoL's tale is being generous since our reality is a direct result of the decisions she made, choices which led to the deaths of billions and wasn't guaranteed to save anyone.

Again, it wasn't a gamble when you know the outcome.

This is a problem because it means she knowingly sundered additional reflections for the purpose of serving as fodder to the Ascians who would rejoin them. So, if they were morally reprehensible, then so is Venat if she were purposefully trying to recreate the events that would lead to the WoL.

Should you choose not to believe that, then we have the Crystal Exarch's timeline, which Veloran in the lore forums noted, is the antithesis of the messaging of EW. They refused to accept their fate after the 8th Umbral Calamity (which was tame compared to the Final Days), labored for 200 years to undo it, and sent G'raha back in time under the belief that in doing so they would all cease to exist. His timeline is the complete failure of everything Venat sought to achieve to the extent that the 'superior' sundered, as we're led to believe, ended up being no different than their unsundered ancestors when push came to shove.