u/AgreeableSuspect3615

Erwin’s first priority in life was to see the basement, he straight up tells Levi this

However, Erwin also struggled with the guilt of sacrificing his Soliders so he could live (he’s shown watching a comrade being eaten)

Him ordering the charge against Zeke only happened because he was cornered and had no way out, and was a glorified suicide for him to settle his guilt to his comrades, he had fully accepted dying in that moment

Now onto Levi:

He initially selfishly decided to revive Erwin once he learned of his survival, despite not being able to name a single one of his accomplishments to Eren or Mikasa, but after he heard Floch dehumanize Erwin as a “devil” who needed to be “brought back to hell”, he started to falter, he makes a discovery, Erwin’s dream ended at the basement, while Armin stated “let’s START at the sea”, meaning he had more dreams for the world, he also remembered Kenny’s statement, “everybody is a slave to something”, but what really decided things was Erwin (in his final act) slapping the serum of out Levi’s hand, showing he was ready to put away his father’s dream and rest, and Levi let him

Levi also doesn’t regret choosing Armin (who saved Paradis by eliminating much of Marley’s armada and navy, convinced his friends to help activate the rumbling to DEFEND Paradis, successfully won over Gabi and Annie to the scouts’ side, and saved the outside world by stopping Eren’s omnicide)

Now imagine if Levi decidedly to selfishly revive Erwin back to hell, imagine how he would feel knowing the 15 year old (who he entrusted to help find Reiner and Bertholdt’s hiding spots) was left to die in order to save him for the 100th time, he would feel extremely guilty, and after he saw the basement and truth he longed of, when he learns that he hid true enemies are basically the same as them? He would feel demoralized, he finally saw the truth, but at what cost? He can’t leave the military due to possessing the literal “god of destruction”, but he would be a more sullen and less charismatic leader, not wanting to fight anymore, and would possibly be demoted, and Hange would take his place.

Then there’s Eren and Mikasa. They would NEVER forgive Levi for letting Armin die, and would likely leave the military, losing the literal founding titan and greatest solider.

Erwin’s final fate would be getting targeted the now earlier formed Yeagerists in this timeline

Erwin’s first priority in life was to see the basement, he straight up tells Levi this

However, Erwin also struggled with the guilt of sacrificing his Soliders so he could live (he’s shown watching a comrade being eaten)

Him ordering the charge against Zeke only happened because he was cornered and had no way out, and was a glorified suicide for him to settle his guilt to his comrades, he had fully accepted dying in that moment

Now onto Levi:

He initially selfishly decided to revive Erwin once he learned of his survival, despite not being able to name a single one of his accomplishments to Eren or Mikasa, but after he heard Floch dehumanize Erwin as a “devil” who needed to be “brought back to hell”, he started to falter, he makes a discovery, Erwin’s dream ended at the basement, while Armin stated “let’s START at the sea”, meaning he had more dreams for the world, he also remembered Kenny’s statement, “everybody is a slave to something”, but what really decided things was Erwin (in his final act) slapping the serum of out Levi’s hand, showing he was ready to put away his father’s dream and rest, and Levi let him

Levi also doesn’t regret choosing Armin (who saved Paradis by eliminating much of Marley’s armada and navy, convinced his friends to help activate the rumbling to DEFEND Paradis, successfully won over Gabi and Annie to the scouts’ side, and saved the outside world by stopping Eren’s omnicide)

Now imagine if Levi decidedly to selfishly revive Erwin back to hell, imagine how he would feel knowing the 15 year old (who he entrusted to help find Reiner and Bertholdt’s hiding spots) was left to die in order to save him for the 100th time, he would feel extremely guilty, and after he saw the basement and truth he longed of, when he learns that he hid true enemies are basically the same as them? He would feel demoralized, he finally saw the truth, but at what cost? He can’t leave the military due to possessing the literal “god of destruction”, but he would be a more sullen and less charismatic leader, not wanting to fight anymore, and would possibly be demoted, and Hange would take his place.

Then there’s Eren and Mikasa. They would NEVER forgive Levi for letting Armin die, and would likely leave the military, losing the literal founding titan and greatest solider.

Erwin’s final fate would be getting targeted the now earlier formed Yeagerists in this timeline