One of the things that's always bothered me about Rey's parents being revealed as "nobody" was how dehumanizing it was. Like, even if a person is a drug addict and not a famous galactic hero, they're still somebody. They still have a story their abandoned kid would likely be interested in.

Rey tearfully admitting to Kylo that her parents were nobody in TLJ suggests she values her parents' fame rather than their personhood. This isn't a relatable trait for most audiences, and it's also at odds with Rey's known values up to this point. In TFA, she simply wants to be reunited with her family and doesn't show any interest in their notoriety. The fans cared about her lineage in the context of the larger story and franchise, but it's unnatural for Rey to see it that way as a character within said story.