I can understand the rationale behind not hiring a "gamer" to make games. Being a gamer isn't enough, if games are your passion, that's not enough to be a good game designer. Spending your whole life playing video games will lead one to developing a concept of what their "ideal" game might be, and then they will fixate on that concept and never give up the pursuit of it becoming a reality, but they will not have the life experience or knowledge necessary to pursue it because their entire life was dedicated to playing games.

If you hire someone who has life experience, and knowledge on various subjects, they will be more adept at making a game but that doesn't mean the game they make will be good, because they still have to have a passion for it, but that passion must drive what they know needs to be done to make a game good, rather than fixating on what they consider their perfect game.