A Turner Hayes or a Cole Young is a generally frowned upon trope in TV or Movie Media in the Modern Age, where in which when adapting an already popular franchise with plenty of characters in it, the studios feel the need to create a completely one note, milquetoast character to be the protagonist and never show up in anything else. The term originates from the character Turner Hayes from the CW Show "Gotham Knights" and the character Cole Young from the 2021 Movie Adaptation of Mortal Kombat.
"I'm sick of all of these "Turner Hayes/Cole Youngs" in shit, just use characters people already know" - A salty redditor.