https://screenrant.com/young-sheldon-season-7-mary-villain-george-sr-story-ruin/

Focusing on Mary's struggles in Young Sheldon season 7 does set up The Big Bang Theory's version of her, but this also ruins her story with George Sr.

Young Sheldon Brings Back Mary’s Worst Traits (Before She Becomes TBBT’s Villain) (https://screenrant.com/young-sheldon-mary-worst-traits-return-before-big-bang-theory-villain/)

Ahead of her villainous arc in The Big Bang Theory, Young Sheldon season 7, episode 6 already brings back some of Mary's worst tendencies.