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

[Teraq]

Honestly, yes, the English localisation often ends up unnecessarily vague. As pointed out,

I just listened to the cutscene in Japanese, my Japanese isn't perfect but she seems to be saying that Hydaelyn was around to bind Zodiark when the Final Days were happening so she would know what to do.

(Or maybe she knows something because the Final Days remained forestalled even though she bound Zodiark, like I said. Not perfect.)

this is also what is said in French, in which Y'shtola specifies that she is referring to Venat being around when Zodiark was summoned to stop the Final Days (implying she would have more context than them) and "forestalling the (implicitly now-current) Final Days" by keeping him alive. I can't speak any German but I am willing to bet their version is also much closer to the Japanese, according to hearsay. It's mostly the English localisation going off.

There are... a lot of other examples like this, though not necessarily pro-Hydaelyn / anti-Zodiark. Some that come to mind due to my area of interest and shameless bias, though: the "patronising" Amaurotine that chides you on your extravagant outfit in Amaurot is "charitable" in French, the "bitter" Ancient in Venat's artistic license version of the Sundering is "bewildered" (presumably by having just witnessed a famous and respected person draw her weapon toward them – understandable, have a nice Final Day), Igeyorhm in Elidibus's second Echo flashback in 5.3 does not just say "some thought you would be unfit for the position" but actually specifies "some thought you would be too kind and indulgent", which is minor but I would argue the English ver diminishes characterisation; his Ancient self being specifically referred to as a young adult in every version but English that for some reason still plays coy with weasel words like "youth" and "boy", leading some unperceptive people to still think he was a child... and how could I forget, his not-so-final line of pure self-abnegation in which he says matter-of-factly that he had to be the last of his kind to go as he would have hated himself for leaving his surviving friends to fend alone... which, yes, the now-famous English version of this line is certainly beautiful and tear jerking because of the callback to the Echo line and posting it on any social media in summer 2020 would have gotten you all the updoots, but I feel it doesn't carry exactly the same explicit meaning.

I'm also low-key mad English Endwalker doesn't have him refer to Hydaelyn as "my dear Hydaelyn" while saddling her with the role of the last of "the authentic human race", as "a last revenge from Zodiark" in his parting lines. Take note, English team, that's what you may refer to as a bitter Ancient.

All in all, these little things can sum up and amount to a different interpretation of characters. Some differences are expected due to the difficulty of translating, but when it only happens with the English localisation I am side-eyeing pretty hard.