“[Leia’s] brother’s saber.”
I don’t remember off the top of my head how many times this is brought up in the film, but would it be feasible to adjust the mentions of the saber to occasionally be “your father’s saber” or similar? Even taking just the OT into account, Luke had that blue saber for what, three years ANH-ESB, before using the green one for the entire rest of his life as a Jedi Master pre-exile? And then of course if you consider TCW and ROTS as well, that saber also prominently becomes the one Anakin used throughout the Clone Wars, and with which he killed most of the Jedi Order. It just seems to me like another instance of the ST looking towards what’s iconic about Star Wars as a real world cultural phenomenon (Rey Skywalker!), rather than considering what’s transpired in universe.