Is it your contention that because we faced two of our toughest enemies in the game, people are
obligated to die or is it because that'd be something that you personally would find more interesting? Nothing happened to the Scions before the Hades fight because he was playing with his food. It wasn't
just implied, Emet stated it himself:
"If I were to bring my full power to bear, you would be scattered like leaves in the wind."
He was purposely holding back just to prove a point. As for that section of the game not happening, the reason it happened in the first place was because Emet-Selch was still operating on the premise of making the Scions understand what it was that the Ascians were trying to do. Sure, it was more so an invitation for the WoL to head to Amaurot and quietly go insane, but that was his final token of good faith. He was confident in his victory after that and would've won had it not been for Minfilia having enough foresight to allow the WoL to rejoin with Ardbert.
Quote:
They constantly teased Yshtola’s death and nothing came of it. They constantly teased Graha’s death and nothing came of it.
Nothing came of Y'shtola's death because of Emet-Selch. As you know, him pulling her from the Lifestream in the same manner the Elementals did was a pretty convenient way for him to gain the Scions' trust
and set up the massive lorebomb regarding Amaurot and the required threads for Endwalker to even be a possibility. Also, if that section of the game regarding The Tempest didn't happen, what then? The WoL would've died of Light-cancer, turned into the most powerful Sin Eater in existence and coup de grâce'd the First. The end.
That and G'raha did, effectively, die. It just wasn't at the climax of 5.0, which seems to be your main contention regarding that point. If you think about it, there's only a few circumstances in this game where death is an indefinite consequence, otherwise, characters face death all the time with no way to circumvent it. This was established back in ARR during the discussion of how Ascians were able to reincarnate after "killing" them. G'raha managed to survive his ordeal with Elidibus because of a plot device established back in the first grind, replicating a dark crystal.
I feel like the longer we have this discussion, the more I feel like you're missing the forest for the trees with these particular takes.
As for plot armor, I'll actually give that to you. The Scions have a lot of plot armor, but none of it is unearned and plot armor isn't necessarily bad, either. You might disagree, but this isn't the first time in media where the main cast survives up until the point of the finale to further cement that feeling of shared growth. Sometimes plot armor is necessary to supplement the wider, overarching narrative.