There's some supposed shortage while we see tons of electrope all over Alexandria.
The same white auracite and his blood was a joint effort between G'raha and Beg Lugg. Just like how it was a joint effort for Alisaie, who has basically no knowledge on the subject of souls to devise a cure when she collaborated with them. The knowledge which eventually evolved to be able to be mass produced with the help of Matoya. The same cure for Levin Sickness that plagued the Alexandrians for centuries because it was damage to the soul that they cannot figure out how to mend -- this cure promptly gets left out in the story.
That should be raising a lot of red flags on how 'developed' the Alexandrian's understanding to the soul is. They have very specific knowledge on memory preservation of a soul, but not much else. Knowledge that the scions could have easily collaborated with, improved upon, and shown Sphene there is definitely an alternate solution if they just worked together.
They shot themselves in the foot because they already wrote the solution to this too. When they had less life aether, they mention the terminals would reincarnate less Endless. Therefore, they could just ... dismiss all the current Endless so they aren't using life aether at the moment to drastically reduce the consumption of Life Aether to the bare minimum. That would have brought us so much time to actually research on a proper cure. Now that's no longer possible because we shut down the terminal -- which is completely different than having the terminals go into super low energy saving mode because all the stored memory are erased upon shutting the terminals down. Even worse -- because there would be Endless that refuse to disappear even if you cut their connection to life aether away, Sphene and the scions would have paid attention to how the Endless can continue to exist without Life Aether being supplied to them. The discovery only improves as they realize they don't even need their memories stored in Electrope to maintain their existence (The Terminals were fully powered down but the Endless can still persist).
I just don't know what to say when I see all those huge inconsistencies in writing. They just didn't even try.