Endwalker was "meh" (for reasons other than technical issues)

[KatsuraJun]

Yes but you don’t know of them until you were level 87 or so, which feels a bit late in the game to introduce a big baddie which you’ve never previously interacted with or established any connection with.

That's because Meteion isn't the villain. The "villain" is philosophical argument that corrupted her, and it certainly didn't come out of nowhere; it's been a part of the game since the beginning.

She's just a piece of said philosophical argument, which serves as the thematic center of not only EW, but XIV itself. In real life ー in the face of our increasingly secularized world, religious institutions argued that a loss of faith would lead to a loss of purpose in living and self-destructive nihilism. For the faithful, God provides meaning, and Meteion's creators are the closest things we have to gods in FFXIV, literally shaping their world as they see fit in paradise. But even here among the gods, Hermes could not find the answer for why we live. Thus, he looks to the stars for answers, but what Meteion finds is emptiness － nihilism, and as Hermes falls to despair, so does Meteion, when her god cannot provide her purpose.

But that is because the answer to living was always within ー internal, not external. The story is literally about exploring Nietzsche's concept of "God is dead," where we find that every one of the gods in our world, once examined, are not really gods at all, and thus it falls on us define the purpose of our existence.

• In ARR, we are questioned why we don't simply call down the Twelve in defense, if our gods are real. The entire casus belli of Garlemald is to force us at gunpoint to abandon our gods, after all.
  "For the world of man to have meaning, man must own the world!"
  
• In Heavensward, Ishgardians struggle with the fact that the Halonic Church that's literally defined their purpose for living for the past millennia is based on a lie.
  "You reject my divinity, yet what have you to offer my people in its stead? Bitter truth? Virtuous suffering?"
  
• In Stormblood, we meet Zenos, who represents the dark mirror half to the existentialism of the Scions, and what people feared existentialism would bring about ー uncaring humans who answer to no god, and thus are morally inculpable to whatever cruelty they desire.
  "We tower above the gods! You by your gift, I by my might! And before the Resonant the gods shall be made to kneel!"
  
• In Shadowbringers, the entire basis of our counterargument against Emet-Selch is an affirmation of existentialism; it is neither Gods nor Ancients that gives value to our lives, it is found within ourselves.
  "We define our worth, not the circumstances of our creation!"
  
• And finally, in Endwalker, we discover that even the benevolent mothercrystal that watched over and protected us ― the closest thing to a true god in the setting of XIV ― was nothing more than a construct crafted by humanity to end our own godhood, urging us to find our own strength and Answers within.

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