Last season I was a heavy erentil user. I was doing a wishender erentil loadout to combat shotgunners and lunas/not forogtten users.
This season I have found my love for shotguns. I have finally got to a skill point where I can use shotguns effectively (when I started this season with shotguns I was getting battered). During this weeks iron banner I was faced against someone with higher power using erentil. There was a big gap between us and I knew I was in kill range for the erentil. All I did was strafe as they charged up and they got at least 70- 80% of hits on me. With that sliver I closed the gap and just popped them with my imperial decree. I tried dustrock blues but it just isn't for me, I'm more of a high risk high reward player.
Getting that kill was very satisfying. You just have to adapt and outmanoeuvre.
Edit: I should have put that I don't mind fusion rifles in their current state. They are easily countable and you can bait the erentil user into committing their charge into a shot just by strafing in and out of cover. If Bungie did nerf fusion rifles they would have to put up for a whole year of people putting "So...nerf fusion rifles" after everything they say. There's a twab somewhere where they very firmly said, "So..nerf fusion rifles...WE GET IT".
Edit 2: I provide this video as a testament to my erentil days in comp: