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.
The point is Rey should have been far more tempted to the Dark Side then Luke because of the environment she was raised in.
I disagree with the notion that people raised in bad environments are led into having questionable morals, and I really like that in the ST (or at least, TFA and TLJ), Rey was screwed over by the world, had parents who abandoned her, and lived a shitty life, but still had a moral compass that pointed north. Kylo had it made, and had parents who loved him, but he still turned to the dark side.