Simply, Rey is not Luke, despite the films treating her like she is, and I honestly think it’s a reductive treatment of her character. She has a different personality, different goals, and different relationships.
Evening Servii.
Luke is the farmboy from Kansas, raised with the good simple virtues of the farmer. Rey is a scavenger in a much more harsh “dog eat dog” world. The obvious way to make Rey different is to show her as a much more hardened, cynical character as a result (more Han, less Luke). Disney probably worried this portrayal would not make her likable. It didn’t hurt to make Tony Stark a bit of an asshole in Iron Man…but I digress.
The point is Rey should have been far more tempted to the Dark Side then Luke because of the environment she was raised in. Come to think of it, in SW77, Luke is pretty much a golden boy. We never get a sense that he could ever be “seduced” by the darkside. We are told in the later films of the dangers, but I honestly never felt there was real tension in ESB or ROTJ that Luke would turn evil, at least until Vader threatened Leia right at the end of the Trilogy.