It's probably to keep the super regen out of crucible. I don't know how effective this exotic is but I'm going to assume it's pretty decent otherwise it wouldn't be an exotic. And even if it DID work in crucible, chances are that it wouldn't be very effective anyways because of how potent super regen is and how careful they are with it's generation...except on chaos reach. So you are at a crossroad where you literally can't use it or it's crippled so much it's not worth using. So they went with the move that pretty much made no difference and that's barring it from pvp as a whole. Sure, having access to it would have been better, but both you and I know that warlocks wouldn't have been pleased either way if it wasn't good...which it wouldn't have been anyways. I can certainly understand though that is annoying...but your frustration seems more about the class as a whole and not exactly the exotic itself...which is likely the only reason you even care that it can't be used in pvp in the first place. Thresh was disabled for a reason and they've already nerfed pretty much every single super regen exotic in the game for good reason. The only two which have escaped nerfs or pvp tuning are doomfang (which requires a void charged melee kill which is not very easy to get in pvp) or chaos reach which only grants that last 15% of super energy. Although people aren't going to like that I say this...i can foresee them nerfing chaos reach's super regen in pvp because of how popular it is right now...and rightfully so because it can be spammed so easily with the cancelling, energy you get from traces (which proc on EVERY kill) and geomags. It's so much fun to use and I've been TELLING people that it's not garbage like they thought it was for the exact reason it's good right now, because of it's regen. I've used it quite a few times before anybody even gave a damn about it and I have gotten it like 3-4 times in a single game of elimination because of the energy from traces, the cancelling and geomags. If that's not really good then I don't know WHAT is.