Quoted for truth.
The Burnham one is just something else. The creators of the show went out of their way to show she's terribly flawed. Captain Kirk or Jean Luc Picard she is not. The reason people take issue with her is because they aren't comfortable seeing a black woman in a leading role who isn't a slave, housewife or some sexualised object placed solely in the film for male gaze.
Regarding Rey, like I said earlier, shes overpowered and has been written as near perfect. Still doesn't make her a Mary Sue because she's not a creator insert and shes the protagonist. A level of competence and bad assery is required.
If folks cant make reasonable criticism of Rey without dragging their personal politics into it or centering it around her gender, then said folks are sexist and might want to re-evaluate their value system.