It's one of those that looked good on paper, not so great in execution. They probably didn't expect to see so many people have it, so many to utilize it so well or for people to make the bosses look like complete jokes. They underestimated the players there I think. Probably waited this long to change it because they were trying to figure out how to kill the infinite ammo without rendering the gun useless. 18 shots before bonus ammo perks from armor is no small amount for a sniper rifle, especially with how common special ammo is in PVE.