I think the big reason people don't want to do it is because of the time and effort you have to invest in doing a new fight, especially when a ton of people haven't cleared ifrit extreme. The earring is pretty much best in slot for any job but the fact that its an earring makes it fairly subpar in general when you compare it to the rewards for all respective primal battles and the upgrade that they give compared to the gear youd be using before getting that upgraded weapon.