If you listen to the majority, it's less efficient than farming marks and rep. If that's true, then it's not so lucrative that it needs to be patched.
It does illustrate a design problem though, which is that level 1 mobs can drop the best gear in the game. Everything I've seen suggests that they've done this so as not to fragment the playerbase into high levels and low level players, and give high level people the incentive to play with lower level people. For example, the fact that a swarm of level 1 enemies can still kill a level 25+ player if they're not careful is further evidence of this. They want high and low level people to be able to play together.
I'm not sure if they achieved the right balance, but having worked on a major AAA game, I can definitely say for sure that they've thought about this. And if you find yourself saying "Why don't they just do X, it solves everything", then you are almost definitely wrong. I hope they continue thinking about this problem though, because obviously a robust loot system is the core of any loot game.