There might be better analogies that fit. "A bit scrawny" is not actually an outright disadvantage in wrestling. Since there are weight classes, a 'scrawny' person facing off aginst a 'hefty' person in the same class probably has height and limb length advantages. It calls for a different strategic approach to dominating the opponent, that's all. If my arm is bent at the elbow while yours is straight out, I can do almost anything I want with it. If we're at a standard start and working towards an ankle grab, my long arms and body mean I can reach yours easier than you can reach mine.
So scrawny vs. hefty isn't an outright advantage to one, it's different kinds of advantages for each.