Wasn't really a unique style considering Moze has an entire tree dedicated to an infinite ammo playstyle.
If nerfing one skill, one of three action skills, and one augment is more than enough to ruin a character then it's time to start talking about how FL4Ks trees are shit and he's a poorly designed character. No character should need to rely on such a small amount of skills to be worth using.
It's a classic ARPG burst style build but it shouldn't rely on three things so low in the trees. It should be a large combination of things all working together, not all of them standing on one skill. Frankly if a 3 point tier 1 skill is that powerful that it's mandatory for the character to work then the skill was OP by every definition.