In my AD&D home campaigns it's often a matter of what area you're in.
It will depend a lot on what rules someone decides to use for the setting.
A lot of settings (Especially video games) tend to use the rule that you're not actually running around picking up loot off people for the most part, but you're already fully equipped (Aside from a few particularly noteworthy magical artefacts). Which is a means to bypass the illogical nature of magical morphing equipment sizes (For example, how a Female Gnome is apparently able to equip Ketheric Thorm's personal armour). With the whole "Looting" business being more of a game mechanic than a lore one.
Whereby the idea of running around looking like a hobo that was struck by a hurricane in a thrift store makes little sense. As why would anyone choose to dress like that.
Like, literally other media outside of games, never has the heroes randomly going around looting crap off their enemies and looking like clowns (With a few exceptions, there are some novels where someone picks up some items but it's not very common). It's very much a "Game" related mechanic that doesn't make a whole lot of logical sense, but provides some more interesting gameplay.
I didn't have the chance to check out the world of Divinity yet, but it's actually a thing in tabletop D&D as well, that some items' magic will work by just carrying them.
Though even in D&D the rule is patchy and strange at best. Especially when it comes to Wildshapes and Druids having magical items literally meld into their flesh but having them stop functioning most of the time. As well as limitations for things in your backpack despite the fact that you're still "Carrying" them.
Still, certain things don't make sense. Like getting an AC bonus from a shield that you're not holding (Unless it's specifically in effect only for attacks from a direction in which you're carrying it)
