This is something that keeps me worried at night. Unlike other historical artefacts like pottery, vellum writing, or stone tablets, information on the Internet can just blink into nonexistence when the server hosting it goes offline. This makes it difficult for future anthropologists who want to study our history and document the different Internet epochs. For my part, I always try to send any news article I see to an archival site (like archive.ph) to help collectively preserve our present so it can still be seen by others in the future.
To be realistic we need to pick and choose what to keep and expend effort/resources on those chosen things.
Without a technological breakthrough in data storage at some point there’s got to be some kind of triage done. We all generate more information now than ever before, and this trend just keeps increasing. With things like A.I, XR, the metaverse or other similar concepts it’ll also get exponentially more insane how much data we generate. It’s not realistic at the moment, technologically or financially, to keep all of it in multiple geographically distributed copies, in a format that will last forever. For a lot of people or organizations it’s not even feasible to keep one copy in some cases due to costs.
To do otherwise we would need a breakthrough that enables insanely cheap, infinitely scalable storage, that is immune to corruption (physical or digital) and optionally immutable to prevent modification. It would have to function in such a way that any reasonably advanced civilization can use the basic laws of physics to figure out how it works and consume the contents without any context of what the devices are. It would also have to work regardless of how fragmented it is, to use terms of today’s technology if they only find one hard drive out of what used to be a pool of 100, it still needs to work on some level.
It’s an interesting thought experiment and hopefully there’s some ridiculously smart people working on it.