What are you talking about dude? Arms in dungeons right now is demolishing Fury and in the raid sims that just released Arms is also slightly above Fury. Arms due to DBTS synergy with Anima is also stronger in Torghast (because you can become unkillable vs melee bosses).
Arms and Fury are both in the bottom half of performers on pure single target, Fury has decent sustained AOE/Cleave but that’s about it, Arms dreadnaught + Condemn cleaving is really strong this week, one of the strongest dungeon specs.
Only the OP specs like MM Hunter and Unholy are really standing out ahead at M0. Arms right now this week is better than Fury at most everything. Where have you even got these ideas from?