Do anyone even call her savior? If anything, it feels like the character was forced into that role, and it's one of the writing choice that felt the most weird with me. She never gained the status she was given.

Someone once told me that the whole "family duty/inheriting something because of your family and not your abilities" was a trope heavily used in japanese fiction, which could in some way explain things, but Lyse never showed any leadership skills, and the whole Doma part that should have taught her that never really achieved to convey that she learned to be a leader there. I always felt it was one of the reason Lyse was disliked : the scenario wanted to push her in a position she never really earned.

So it feels really weird to me that people discuss about her being a white savoir, when she never saved anything. Someone just went "I knew your father, so you should lead the resistance" and everyone rolled with it.