A thing in videogame balancing where damage over time is involved. There is a very thin line of making it useless or "OP" I am sure they are taking careful consideration onto the balancing of that weapon, as for BadJuJu, no clue why isn't this buffed yet. And also I think it is for all underperforming exotics, like Super Good Advice, Midas, Truth etc So there will likely be a patch containing all of them.