Xur sold suros twice, so it became pretty widespread. Yet there were people who, for some reason beyond me, didn't buy the best auto rifle in the game. They in turn bitched, and then suros was nerfed. The same will happen to gjallarhorn. There will be people who won't buy it for whatever reason. Then will come the bitching, then the nerfing. Not to mention, the gun is insanely OP, and once bungie sees people flying through everything, they will nerf it.