I really don’t see MM as having bad survivability issues compared to other DPS. So, I don’t quite buy into the glass cannon argument. Ranged classes, in general, have better survivability than melee in BGs just by simply having good positioning.
And, even if something gets on them MM has tools to deal with that. All of the traps, explosive trap, tar trap, freezing trap, steel trap, disengage, feign death, cheetah, master’s call, exhilaration, turtle, fortitude of the bear, roar of sacrifice, intimidation, scatter shot, binding shot, bursting shot, etc can all be used defensively.
Of course, you won’t have all of this but you can have most of it. If I die with all of my cooldowns available I typically feel that I just misplayed or got outplayed in the fight (or got overwhelmed with numbers, but everything dies to numbers).
MM hunters should have one of the best Kill to Death ratios in the BGs even when solo queueing. If not, then they are doing something wrong.