Balance and symmetry I think
Collectors and museums have a responsibility to return these artifacts to their country of origin if the artifacts were stolen through acts like colonization. Take Ancient Egypt, for example. British archaeologists and historians excavated the tombs of Pharaohs, completely ignoring that in Egyptian culture, the Pharaohs needed those artifacts the archaeologists extracted to safely travel to the afterlife. Taking these artifacts and bringing them back to Britain is detrimental to Egypt's history and culture, effectively stealing their heritage from them. But, museums also have a responsibility to spread easy access to history all across the world. They can do this, but with replicas of the artifacts instead of originals. This allows Egypt to keep its heritage in its own Pyramids and museums, while still being able to share that history with the world.
