I need to stop interpreting TTK as The Taken King whenever I come back to this post. That aside, the potential of a Scout Rifle is much more heavily dependent on the wielder's own ability than other weapons tend to be. As a seasoned SR user, I find them easy to play with. For someone who is an infrequent player, they'll likely want to use the weapons that are easiest to do well with - the exact opposite of Scout Rifles in this meta.