The way TLJ is written, the whole “your parents were nobody” was all Kylo trying to turn her. So it being the unvarnished truth doesn’t make a lot of sense. The way TROS was written, Kylo carries on from where he thought he had pulled her down with the added information that Palpatine was her grandfather. We really have no idea now much that Kylo told her was true until Luke confirms that she is indeed a Palpatine and He and Leia both knew. It can echo some of Luke’s initial hesitation to teach her in TLJ. Really, most of the problems with the ST are not what is in the ST, but how people ran with things in each of the films. Fans latched onto Rey Nobody. Sure, Rey was okay with that. But the key piece was that parents were nobody special remained. Her parents had abandoned any connection to the name Palpatine and were living on the lamb so she was raised as just a person who wasn’t likely to have a place in an epic tale, but the force called to her. Her parents evidently had no force skills so they literally were nothing special. Any inherited ability skipped a generation. So her turning out to be a Palpatine completely fits with what we saw in TLJ. It doesn’t rewrite anything, except for fans who latched on to that and took it as absolute truth. Those who fall to the dark side use pieces of the truth to try to turn or influence other. A half truth is better than a lie. We saw Dooku, Vader, and Palpatine all do it. Kylo doing it is in line with that.