Sources needed. How do we know when the aether was going to run out? Given that Sphene is currently[...]
It could have, it couldn't have. We don't know, that's the point. We potentially had thousands of years, or we could have days. We never tried to figure it out. Sphene is urgently trying to gather more, yes, but has been for some time; yet the Living Memory is still functioning. So clearly there's some amount of energy in storage, it's just a matter now of how long it will last. If she was direly low she wouldn't have the power to fight us, so clearly she wasn't running on E now was she?

If you ignore all the scenes they wrote, then sure. I didn't though. I actually listened when they discussed how there isn't an alternative solution to its current fuel source and that the only way to [...]
Unreliable narrator on one side, fox in the hen house on the other.

We could have listened to Emet-Selch when he said there was no other way. We could have listened to Asahi when he said there was no other way. We could have listened to Ardbert when he said there was no other way. The entire FFXIV plot is founded on us defying the 'there is no other way' statement, and there are nigh countless examples of it across the story. Cah and Sphene were both limited to their own technology, their own means. If you want to say it's illogical to presume we could find another means, then suit yourself but I find that itself to be illogical in a story in which that is the primary function of the WoL and the artists formerly known as the scions.

You seem quite pleased to follow the story as you've determined it to be presented and accuse others of not having listened to the cutscenes or side-content as you've done so twice now. I'm happy you enjoyed the story, enjoy it.

The point is there is moral relativism, there always was, and it's been repeatedly placed across the story. I'm not emotional that they violated the consistency of the story or that they put themselves into a moral quagmire: I am disappointed by the failure to meaningfully engage with having done so and reflect meaningful consequences when that has been a central theme in the story up until now.

We did what Emet-Selch wanted to do in the story as told, then we patted ourselves on the back. So long as they commit to that story I'm fine with it. So I return to my previous statement, all else aside; If we use the logic of a villain to take a course, that is a step into villainy.

If they tied the story up in this sense because 'video game reasons' then the story isn't better for having a reason behind it. You opened up by saying you did not see these issues with the story as told and I will for a third time congratulate you, I'm happy for you. I did, others have, and I would argue it's part of the intended point that people have discussions like these.

Moral relativism, and all that.