What they did with Zodiark surprised me in how much it actually didn't surprise me, if that makes sense? I felt in my gut that there was no way that Zodiark was 'Final Boss' material, and I guessed/hoped that if we did fight Hydaelyn in Endwalker, it was either an outright test of our strength to prove that we were strong enough to fight Zodiark and then whatever the Final Days cause was (I was mostly right about this) or a fight against Hydaelyn to change her mind that we would be strong enough to defeat them and that she needed to have faith in our abilities and give us her trust (which, turns out, she had more trust in the mental/emotional/physical strength of Sundered life and the WoL as its representative than she did in herself, nice). So I was expecting the order to be swapped. But doing more with Zodiark than they did would have felt like unnecessary padding. We were primed by Shadowbringers to be focused on the Final Days. Zodiark didn't cause the Final Days, nor was he a way to solve it, thus he couldn't take over what our focus had to be. (Does this hilariously make Zodiark even more like Zenos, a mostly flat one-dimensional antagonist that turns out to be the Team Rocket side issue?)