Q u o t e:
Same reason volley was nerfed, FoK is too strong.

This, basically.

For PvE this certainly is a nerf, but in fairness it was a nerf that was well earned. This doesn't mean rogues can no longer provide AoE DPS, and it in no way compromises the performance of a rogue to the extent they will be benched from now on. It was simply to potent without a realistic way of having it countered.