Bungie wanted to separate it from the rest. It has many advantages over the other exotic ad clear explosion and the legendary weapons with the cursed thrall trait to make up for being the only precision based one. 1. The perks. Desperation increases the stability to 100 and while not known how much aim assist it gives it probably gives +10 which gives it 95 aim assist and it becomes insanely easy to hit future precision hits. 2nd perk one for thrall gives it a pretty big bump in stats. Not certain how much it gives but I think it's +15-20 with one for thrall active for both handling and range with aim assist being tough but it probably gives +5-10 and maxes out aim assist when active with desperation. Also desperation increases the rpm to I believe 900 though some believe it might be slightly higher than 900. And unlike desperado it doesn't have the damage penalty (Desperado used to give a similar rpm buff but at the cost of 20% damage now it only increases rpm by like 50 for each weapon but doesn't give a penalty) 2. Is the damage. Easy enough to just say it basically deals double the damage of other explosions the only explosion that deals more is the 3 kills in a row explosion from Choir of One. It also poisons enemies and any enemy poisoned by Necrochasm will explode as well if killed by either Necrochasm (Body or head doesn't matter while poisoned) or the poison. It has some big advantages in return for precision only though I'm on pc which 720 autos are much easier to control on pc than on console so I can't really say how it performs on console but it's pretty much my go to ad clear weapon on pc.

The desperation perk is essentially the desperado perk - headshots increase fire rate. The explosions are additional to this.