So I've only recently gotten into Genshin so this is probably, definitely completely bullshit but! Headcanon:
Nahida could have, technically gotten herself out of the Akasha. She's a god ffs and she is powerful even without the gnosis or her people's belief.
The reason she didn't, whilst originally because of the Sages manipulation, was actually because breaking out of the Akasha would have resulted in major backlash within the system that would potentially kill or injure anyone wearing a terminal at the time. These things are hooked into the wearer's brains right? So sudden glitches or power surges within them could be really dangerous.
I am almost definitely maybe talking bullshit but the idea stuck with me. Nahida is so smart, even if they did convince her that sumeru was better off without her she had to have considered running away and disappearing. They have her gnosis they don't need her to power the Akasha. Nahida thought about leaving but didn't because even attempting to leave physically ran the risk of killing her people. And she loved her people, even when the sages had her convinced that she was unwanted and unneeded she loved them. She would never risk their lives.
