Something I've noticed since the launch of forsaken and the TTK update is that SMG's don't have a large enough niche to operate in. The effective range of most SMG's is severely limited by their recoil pattern. Even with counter balance stocks equipped, almost all SMG's are extremely difficult to control and are extremely unforgiving.
SMG's effective range overlap with side arms, and chaperone on the close range side, and hand cannons, as well as AR's (though they are slighlty underpowered too) and fast shooting pulse rifles on the close-mid side. SMG's have to compete with the most powerful PvP weapons (shotguns, side arms, hand cannons), all of which are strong in SMG's optimal range. To make SMG's more viable in the current META, recoil patterns need to be more controllable to make SMG's more competitive in close and close-mid engagements. Currently, the antiop is the only SMG which is able to excel in close to mid ranges.