I sort of beg to differ. He’s unstoppable to the point of having magic power in a “realistic” universe. Rey is just a particularly quick learning wizard in a universe that has wizards.
Yeah, while I LOVE the Reacher show and think they nail the pulpy fun tone they are aiming for (and Alan Richston is fantastic), I don’t think you can accuse Rey of being a Mary Sue but then excuse Reacher.
The Reacher character is basically like if Drew Brees was also Sherlock Holmes, Captain America, and Thor.