I think many view this Reacher character in a similar way they viewed Geralt in The Witcher. The problem is the stoic, almost wooden at times portrayal of both is actually how the characters are written in the source material. It's perfectly fair if a viewer doesn't find that sort of protagonist interesting or showing enough depth but it is what it is if show is trying to stay in canon.
It's bugging me that I thought I recognized Rosco (Willa Fitzgerald) from something else but after checking her filmography it's gotta be someone else.