When you frame it a certain way of course it sounds awful. Let me try the opposite.

Lae'zel has been indoctrinated since birth by a crazy religious and xenophobic culture. The second she's told she's being lied to she doesn't believe anyone because people don't change their mind about their entire belief system through one line of dialogue from a person she just met.

However after a few more hard facts being shown to her, such as said religious culture trying to kill her and being lied to by the head of said fanatics, she realizes all of her people are actually indoctrinated slaves and starts to fight for the future of her people by rallying around the one person who can actually do something to stop it all.

Not sure why her breaking away from the brainwashing and indoctrination and trying to help free her people after seeing the truth is a bad thing here? Also fun fact, if Orpheus turns into a mind flayer and dies at the end she goes to free her people anyway, it wasn't just about him. She didn't just become a zealot following a new person, she became dedicated to freeing her people. Orpheus has that capability so she wants to free him.