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

[Theodric]

A common take has been that it's perfectly justified for the Sundered to do everything possible in order to survive. On the other hand, the same can be said of the Unsundered - it's a reasonable expectation for the Ascians to do whatever is needed to ensure that their people aren't wiped out.

Shadowbringers took that approach and presented it all as an unfortunate but necessary clash of like wills. If Emet won, his people would be restored and the Sundered would be no more. On the other hand, with the Warrior of Light's victory it was the Ancients who were eliminated in their entirety. The problem, then is that it is Venat who put both sides in such a horrific position in the first place but all sorts of contrived plot devices are pulled out in order to try and awkwardly justify it instead of just straight up admitting that it was pretty abhorrent and selfish of her to do as much.

Worse yet, the Sundered didn't even pass her 'test' because at various points they required the aid of not only the Unsundered but various other powerful entities such as the dragons and Omega in order to succeed. The victory against Meteion wasn't entirely their own doing, thus 'Dynamis' comes across as little more than a sad excuse to try and pretend as if the Ancients 'deserved' to be wiped out because they couldn't wield it effectively. (Which has unpleasant implications - especially when Garleans are unable to wield Aether as well as the other races and led to their persecution and near extinction...)