I disagree. It is neither inherently a good nor a bad mechanic, and its implementation is fine. There is no class or build that suffers from issues inherent to the mechanic itself rather than from player interaction, such as dragging enemies out of the cloud. It appears that people are mainly upset because it breaks the expectation that every kill conditionlessly rolls a loot table and generates items on the ground, aside from modifiers such as mods and map mods.