The Reasoning behind The Sundering? (*6.0 Endwalker Spoilers*)

[Nilroreo]

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Sorry if this has been discussed already but this can't simply be a matter of viewing things from a different perspective as inconsistencies with Hydaelyn's character can be seen even as far back as Heavensward. I recall there being a line back when she used Minfilia as her mouthpiece where she states she's failed at preventing 7 rejoining's, which we now know can't possibly be true since her entire plan hinged on us having come as far as we have. Considering she needed those rejoining's to happen, I'd sooner call them victories on her end.

Also, on the matter of converging timelines, ignoring that this expansion seems to brush aside what we've already learned about time travel in Shadowbringers, assuming that timelines are indeed "converging", I feel most of these changes would have occurred only after our trip to Elpis. Venat at the start of Endwalker mentions honoring some promise she made in another age, and Elidibus's words suggest we will eventually meet him in Elpis, but both of these conversations happen before we've even done anything to change the course of history. The simple fact that characters are referencing events that will, NOT might happen tells me the writers just want us to assume that it really is just a perfect closed loop.