This explains it a better than I could. It's sexist because there is a far lower threshold to what constitutes a mary sue for women than it does for men. The Rey-Luke comparison being pretty apt with how Luke is allowed to gain competence in the force within a short amount of time while Rey apparently has to have a Rocky style montage before she can do anything with it.
Are we still talking about this?
Luke got the shit on the entire movie and had one of the best Jedi ever as his teacher.
Rey somehow knew how to do the mind trick out of nowhere and all this other shit despite not even meeting another Jedi.
I can't speak to whether Mary Sue is a sexist term or not, but in terms of Star
Wars, there really isn't a comparison.