Sharlayan origins and the Endwalker Trailer

[Vyrerus]

...no? Very no, actually. This is abundantly untrue. '

Here's the problem with your assertion. None of those were events that were going to destroy the world.

Ultima Weapon not stopped = Bad times for Eorzea, and perhaps an immediate 8th Calamity.

Thordan not stopped = Ultima had to have been stopped so that events play out the same way, but that means that Zenos has our Echo data and will receive the Resonance procedure, and then will have no trouble stopping Thordan, since that was something he did independently with data given to him by Gaius van Baelsar. Again, no planetary destruction.

I could keep going, but the fact is that none of it amounts to thwarting planetary destruction. It is you who have shifted the goalposts for the protagonists, when the setting has directly spelled out that until Fandaniel, none of the antagonists have been trying to destroy the world. Do it massive harm to enact a weird healing process, yes. Destroy it, no.