From what has been shown, it seems to be that the Devs are purposely doing this.
Weapons that do damage primarily from its base damage favors very large hits from stacking every possible multiplier. (5x Crits * 4x Multishot * 4x Adrenaline Overload Bonus = 80 x damage)
It's a technically a nerf to Monkchers by buffing everyone else's damage by 50-100% using a mechanic that totally ignores critical multipliers and adrenaline overload 300% bonus.
These weapons seem to be doing their damage primarily from elemental procs ~ 130 dmg per hit.
35 Touch of Flames
20 Dragon's Edge
75 Burning Emptiness
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130 Fire Damage Per Hit on a 15-20/x2 Weapon