"For this quest, we'll send you into a different dimension, which is really the same place you're already at, just with a gray filter. There you will have to grind for an abstract item so generic we couldn't even give it a proper name, which only drops from a few mobs, and even those have a drop rate under 25%. For your convenience, the mobs are so far apart from each other that you can't even pull a group, or some of them will reset. So you'll have to kill over 100 of these HP sponges one by one, or at most in pairs (actually, you'll have to kill a lot more, because each of the mobs that can drop it is surrounded by mobs that can't). Oh, but after a few minutes we'll teleport you back to the normal 'dimension', and you'll have to go buy a new 'key' (which requires grinding yet another random currency) and walk all the way back to the 'door' to continue this exciting and fulfilling activity. Have fun!"
Dull, slow, mind-numbing, vexing. This quest is a great summary for Shadowlands as a whole. It's like you're paying Blizzard for the privilege of being trolled.
I guess they were too busy changing the name of a pink rocket from "love" to "heartbreak" (because that's such a positive change, eh?) to actually playtest their own "quests"...