Disappointed in one Endwalker Aspect [SPOILERS]

[Veloran]

Theoretically, the PC could stay behind in the World Unsundered and help Venat (?) stop the OG Final Days, but that raises two big issues:

Issues which disappear if the timeline was simply split. Then their timeline could be saved without impacting our own. As for the trouble of WoL returning to the present, there isn't any evidence of such a thing being impossible, G'raha never even made an attempt for such a thing.

It's the same reason that before Endwalker had even released that I knew the Scions were never going to be killed off, they are a necessary part of the trust system.

I've never understood this argument. We see in Elpis that new Trust members can be switched in at any time.