Non instance and farming, it sucks or its great depending on who is on that end of the stick. Things like "Lore" was there to limit 1 per toon or legendary for per account, these curb farming. Another way is increase the drop rate or allow another way to get the item, like "Jboots" quest as example, how often items drop or how long the NPC quest mob spawns. This too curbs how many items are in the game or limit farming.
Dev's attention to items having more or less of certain items in the game is their JOB! Not watching for such things with todays coding and lookups is just asinine. Even back then, they knew. Wont blame all on devs as companies do limit funds for things thats a given but dev do have a hand in helping ease the pain. I am sure as expansions carried on they could have added 1 extra NPC or drop here and there to decrease the bottlenecks from past expansions in the new expansion.
One example of this is epics. They did actually do something YEARS later but did do it. I have been waiting years for them to update the iksar quests. Necro hat and Warrior pike. I heard they did like 2 more quest chains not too long ago. Think the greenmyst and shm quests item "crudge?" got some love too, no clue on the mnk.
Notice I said Lore and legendary, not no drop. I cant tell you the hate I have for that little pissant thing. The most game breaking emersion ripping idea with no fantasy bases but for cursed items. Curse you had to seek help to remove it and even then it could come back. In MMO its a tool that cant be explained.
Here son, you can adventure the wild lands, slay dragons and beat GODS but that items you have.....well you cant give it to anyone and if your lucky, some merchant "NPC" might buy it from you for next to nothing or you can just destroy it.