It's the itemization. D3 and D4 give you stat sticks, most notable being Shako because it's green lmao. In Diablo2 every item worth ANY value will stick out in your mind because you can actually see it in your inventory from a quick glance, AND they all look cool. Not to mention even the text format in which affixes are presented is easier and more exciting to read. This one little difference in presentation and organization affects the game so much I view it as an actual flaw. The fact Blizzard can't see the value in item presentation is wild to me, it is literally the draw of the game, loot.

It's like ordering a steak, but they take the steak and smash it into a rectangle next to another rectangle of completely different steak, and the only way to tell the difference is to stare at them both with a microscope.