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

[KageTokage]

3) On that note, Endwalker should have been split into two expansions. Or the initial story should have been entirely focused on Thavanir/a Garlemald that wasn't already off-screen'd, while the post-story should have then gone into the Moon/End Days stuff. Cramming Ala Mhigo and Doma into the same expansion was the #1 criticism of Stormblood, so I'm not sure why the writers thought that doing an extreme version of this in Endwalker by cramming four major regions into one expansion (Garlemald, Thavanir, Sharlaya, and the Moon/Ultima Thule) into the initial story was a good idea.

That's the thing.

Endwalker was originally intended to be two expansions as per some past interviews, with Garlemald slated as being the endpoint for the first of them, meaning the tower business was supposed to be a much more lasting threat then it was.

That would've presumably left the Final Days with an expansion to itself and a lot more time for the subplots surrounding it to develop.