IT SERVES ABSOLUTELY NO PURPOSE aside from breaking the balance of the game.
It has to be one of the worst game design ideas ever to have constant anti healing on certain classes and not others.
If you want anti healing to exist in pvp either make it a active CD for the classes that have it like how sharpened blade works for war. Otherwise remove it entirely.
Its too important in pvp and literally reduces the viability of any class that doesnt have it, not to forget its impossible to balance classes like this. Dampening is enough.
However, on this specific subject i also agree. I said it myself multiple times already that everyone having ms effect is just stupid. Might as well take it away from everyone and reduce healing.