I hear people saying that, but I don't think it's completely true.
Just for kicks, I watched him off the ball in the last couple of games and while he's not a rugged tackler, he does track his man and often does enough to interfere with him to stop progress, disrupt his pass or make him turn back.
Even if he did none of that, though, he should still be in the team for his on-the-ball contributions.
On a different note, the Evening Times says Sloth is "in contention" for this game.