The good part is that there is no major reward for ganking, though most gankers don't need any rewards to gank, just getting to kill poor near helpless people over and over is all that matters.
When the game The Division announced their Dark Zone and how it would have the best rewards and that in essence it would be a FFA, I questioned how well that was REALLY going to work. Anytime you create something like that without some type checks and balances , goon squads will emerge. And in the case of the Division, they rewarded ganking someone zoning in.
I play on PC and my son plays on PS4 and you started seeing the highly geared players forming teams to camp the various entrances and mow people down. My son reported they even had teams working in tandem to cover all the doors. If you had a slow system you would just find yourself zoning in dead over and over.
The underbelly is an interesting place, though I disagree with it. It seems as usual Blizzard creates environments that cater to those who like to grief the unsuspecting. I still question why PvP needs so many gimmicks