With Legion, I feel that Blizzard solved a major source of social friction and then almost immediately made it even worse than before.
As you may or may not know, by default LFD queues in Legion are Personal Loot, which neatly solves the long-standing issue of loot whore/ninjaing. But this also made it feel like nobody was getting any actual loot, so Blizzard added a big prompt notifying when other people won stuff. Of course, this highlighted those situations when someone won useless (to them) loot, and people started pining for the days when they could pass on/trade loot to each other. So Blizzard made the items tradable as long as you already had something with a higher ilevel in that slot.
This culminated in my recent Neltharion’s Lair run, wherein I won some lower ilevel gloves and missed the whispers from the healer after the penultimate boss. Hey, the chat box gets pretty full sometimes with the near non-stop narration, okay? Taking my silence as some sort of snub – or perhaps simply engaging in some vindictive blackmail – the healer simply stopped healing me. After eating dirt for a second time in front of the trash leading to the final boss, and getting emotes instead of a rez, I asked “Did I do something wrong? :(” assuming that I was not following some trash mechanic. “At last he speaks.” Ah, I see. I trade the gloves and received healing for the last fight.
This sort of convoluted situation has since occurred three more times in different contexts. Boss dropped a 825 helm and the Demon Hunter traded it to me, but seemed to almost regret his decision. “Are you really going to use that?” I suppose he was asking since I had the 2-piece set bonus from the Order Hall armor. Another time some gloves dropped and the winner asked who needed it, and two party members must have gotten in a furious whisper war, because the run stopped for a solid 2 minutes before something was hashed out.
Finally, I won some lower-ilevel wrists in my latest dungeon run, and basically spent the rest of the run trying to inspect our Bear tank to see if they were an upgrade to him. They were, I surreptitiously traded them to him instead of the Demon Hunter, and went on with my day.
Hey, remember when all of this was solved by hitting Need or Greed? I do.
Seriously though, if Blizzard is going to add all of this tradable Personal Loot nonsense, they should probably invest in an UI element that asks if you want to Pass on the loot. If you hit Yes, it should pop up a Need or Greed prompt for everyone. If you hit No, the item could still be tradable in case you want to give the item to a particular person without advertising or whatever. Done and done.