Yeah, that doesn’t work still. Her parents being nobody was about her not feeling like a part of this big and important conflict. Her grandfather being the biggest and most important part of this almost-century of conflict does contradict that. It contradicts her emotional arc of having to create self-worth, rather than her importance being externally from who her parents and grandparents were.
Her feelings of worthlessness don’t come across at all in Rise of Skywalker. It’s a feeling that she must be evil because Palpatine is evil. And overcoming that is literally what Luke already went through with Vader. It’s reductive to Rey as a character on a storytelling level, repositioning her again as a proxy for Luke rather than an autonomous character, and it’s also reductive to her arc that she already went through in Last Jedi to learn that she is her own person regardless of who her family was.
It’s just bad writing. Like it all you want, maybe it helps you with the accusations that she was a “Mary Sue” or whatever. It doesn’t make up for the fact that it was bad writing that hurt the character and story. Maybe that can and will be fixed, but it hasn’t been yet.
I put up a link to my post of Rey’s self-worth arc earlier.