Context:
bags dropped on the floor can be lost in so many ways. if the bag is touched slightly, it can become a spaceship and fly into the stratosphere in a random direction. it could also be stolen by a bad actor by simply picking it up. these problems can be easily avoided with changes to how backpacks work when dropped
Solution:
backpacks dropping to the floor causes a lot of problems, so the answer is simple: dont let them. if a player were to let go of their bag, the bag could float in mid air and the player could interact with it with both hands (example: see Into the Radius VR). backpacks floating in the air when dropped sounds like an alien concept, but I implore you to consider it. this would allow the player to more easily sort through their bag, while also protecting it from thieves who would have grabbed it if it were sitting on the ground. this also protects against your backpack becoming a satellite, since they wouldn't be able to move while floating. if the player walks more than five meters from the bag, it will recall back to the player's back similar to how the camera disappears when you walk far from it. this would solve pretty much all bag theft since if the player were to drop their bag in any way whatsoever then it would simply float without anyone else able to interact with it. if the player wishes to have their bag drop to the ground then they could grab and drop the bag really quickly for it to fall on the ground like a physics object. they could also shake the bag like a gather skill. just add a five second timer so no one else can interact with the bag when it is dropped so a bad actor may not say "shake your bag and let go, see what happens." if the player wishes to hand the backpack to someone else they trust, they could wait the five seconds or hand the bag to someone the same way friend cookies are handed to other players.
if you are just super opposed to the idea of the backpack floating in mid air, then i may recommend setting the bag on the ground? similar to how grass clumps can be set, the player could set their bag so that it doesnt move. this would be far more limiting and less intuitive than floating, but it would at least be better than what we have now.
TL;DR
make bags float when you drop them.