No matter what some people say, 99.9% of Eastern players are self-inserters. And no, I don’t mean “for (you)” type. I mean they are actively roleplaying. The whole “you’re not TB” mindset is Western. In the East, no one cares; it’s understood that you’re playing as yourself through the Trailblazer. The shitposts here with "You are not Caelus" just isn’t a thing there. That’s how the game is meant to be played: you are the Trailblazer.
And that’s exactly where Shaoji fumbled in patches 3.0 to 3.4. You don’t connect with anyone. Agalea, Phainon, Mydei, Tribbie, Cipher, none of them meaningfully interact with the TB. Their arcs all play out away from your perspective. You don’t talk to Agalea about her humanity, you don’t engage with Mydei’s warrior code, you don’t really know Phainon, you don’t talk with Cipher about her thievery, and you hardly interact with Tribbie. And Anaxia, you don't even talk to him. These characters are off doing their own thing, and you’re just watching. There's no reason to care.
The only character where this issue doesn’t apply is Castorice. She’s the one person in Amphorous, up to patch 3.4, that you genuinely connect with. Your story and hers naturally intersect, and you become an integral part of her arc. The TB dies on the way to the planet and must recover the lost soul from the Netherrealm. Castorice, cursed to bring death with her hands, is seeking the Death Titan (the same place) for a cure and is struggling with her decision about the Coreflame of Death. For the first time, she finds a life she can save, and that becomes her motivation. Your problem turns into her motivation and resolution, and her determination to save you, exhaling from her personal story, is how you are saved. That connects a player with her. This is absent for everyone besides Castorice and Phainon before 3.5.

A gacha fails when it does not succeed in getting players to care for the characters. That is the problem.