The terrible itemization gave birth to “smart loot” because the only good stats were Primary, IAS, CHD, Crit… I’m not at all complaining about the drop rate. “Diablo” 3 needs a very high drop rate since there’s only a single viable item for each item slot and it has to roll ancient and have the right stats since Legendaries are just Generic Item Templates rather than unique. Generic Item Templates work for Magic and Rare items in D2. D2’s crafting is basically a Semi-Fixed Item Template where you, depending on chosen recipe, have 2-3 fixed stats and some generated ones.
The fact that “smart Loot” wasn’t even guaranteed only made the few times you found an off-class item particularly annoying as “Diablo” 3 is designed around not ever playing multiple classes (Smart Loot, One-time Season Rewards,…)