Yeah, because having every corner mean immediate death is a lot of fun, and scout rifles are useful in all of 2 maps. And there are so many tight corners in Destiny. The shotgun wasn't a problem in Halo because there wasn't cover within 10 meters of every spot on the map. In destiny, every map has tons of thin corridors, hallways and corners, and trucks and terrain that you can hide behind. Hit someone with a scout rifle and if they don't have good range, they just run away. Also the verticality makes it easier for shotguns, since vertical changes are hard for headshots and no problem for a shotgun user. There is also a high enough rate of fire that you can miss a shot and still get the kill, and the small magazine doesn't really matter at all since the places where shotgun users hide are easy to take cover in and reload.