We don't know tons of stuff about history because of lost information. The Library of Alexandria had tons of valuable information. The internet should be a way to get around that but...
Anyway, none of the civilizations in these regions had built nuclear technology, or influenced the emergence of treatment-resistant diseases, or generally altered the landscape to such an extent as we have (dams, holes in the ground, big tall chunks of metal and concrete). It is probably in the best interests of anyone living on this planet in the next few thousand years that they have some knowledge of how we've lived and why. "We built weapons that can each destroy land a day's walk wide because there was a war where the stakes were genocide" is maybe something that shouldn't be forgotten. Any number of other developments are also important. It's hard to tell in the moment what will be so in the future.
Another good reason for widespread archival.-