As for line removal topic, I kind of have a hard time with Luke: “1000 generations are in you” line. We do know … that’s not how that works with Jedi. Granted, he may be saying that in a symbolic sense, but we literally see later that Palps says the lines “I am all the sith” and have that whole transfer silly thing.
So to me … it’s like … another retcon of the movies before it that is factually incorrect.
Again, he may be not saying it as literally having jedi in her or whatnot, but with the whole silly Sith thing later … it makes it sound more literally.
Anyway … that’s just me.
I think the key difference there is solved because of this fan edit. Rey has 1000 generations in her, but the way that manifests is with Force ghosts surrounding wherever she goes. In this case, they appeared behind her and helped her defeat Palpatine. In Palpatine’s case of being all the Sith, I believe he is saying that all of the Sith spirits reside in his physical body, and cannot manifest outside of it.