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

[KageTokage]

Even the Ascians weren't completely destroyed by the methods used to kill them; it seems to just weaken their souls enough for the Lifestream to take hold of them and return them to the cycle as they're meant to.

It evidently takes a lot to make someone deader then dead, with only those involved in Hydaelyn's summoning process and those turned into beasts/blasphemies stated as having their souls completely purged, and the latter case is still uncertain as Meteion wouldn't need to be harvesting souls to deny life if she was actually capable of completely eradicating them.