It affects items that you do not have equipped. Lets pretend for a moment that you have a save from a much older version of the game in which a particular unique weapon had different stats compared to the version you are on now, you might be a little disappointed that this shitty weapon has received a buff making it über awesome sauce but because you found it ages ago, your's is garbage. The bow and quiver will replace all of your unequipped items with new versions of the the same weapons meaning new stats take effect. But the downside is that it removes all upgrades to said weapons.What is the effect that interacting with the Bow and Quiver on the ground has on the rest of the Weapon and Armor you have in that moment?
I haven't tried to active it. Last time I started from the beginning. Doesn't it affects all your equipment?
In this case, we're "exploiting" the fact that it removes upgrades from weapons to work-around the bug with reforging the Tainted Dawnbreaker.