Rey has been called a Mary Sue from the beginning. While I can completely see the reason, I mean, I’ve even said it…But that doesn’t make it right without seeing the final 9th film to truly understand what her story is. In the Force Awakens Palpatine or Snoke spoke to Rey. We also see how she used Palpatine’s attack several times as he fought off Mace and the Jedi. If Rey is a Palpatine or a Kenobi, then I don’t think she can be referred to as a Mary Sue ever again.