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

[Erendis]

She preaches constantly the entire game about having hope, never giving up, making the impossible possible yet doesn’t apply any of these things to her own people, and effectively gives up on them and murders them all.

And for what? Because WoL sounded cool when speaking about her adventures...

I'm already dreading the idea of Alphinaud and Alisae seeding the idea that Garlemald should do away with the idea of an Emperor so it can instead become a democratic republic again.

Why? Garlemald became an empire solely because of Solus. It was a republic 80 years ago, or so.

Garlemald has been reduced to Rubble, its residence huddling in a subways (and it was hinted at that a large amount of citizens and soldiers were un tempered and are undergoing treatment after the tower of babel so they need a more viable living location soon) and it has no current leader or government that people can turn to.

You think this would be the prime concern for the WoL due to how they like helping those in need

What do you want WoL to do? Build some houses? That was always side content.