Moreover, we see the same thing today with digital items. (Well, to be honest, we already saw this 20 years ago with digital items.)
There, it is just not so visible because disk space is ever increasing as well as getting cheaper.
In the days of Napster, people collected gigabytes of music just to have it - at some point this was more minutes than they could ever listen to in a life span.
Few people actually care to collect that stuff in order to make it accessible to more people. For example, the people at archive.org, as well as many libraries, are doing a great job.
But the majority of collectors collect only for their own, usually with an unwieldy directory structures and meaningless file names (track1, track2, ...). They won't ever find anything they search for. It's often faster to search & buy those via Internet. Same with movies.
It is even worse with personal photographs and videos. The same way some people have loads of paper photographs around, other have disks full of digital photographs. 200+ photographs per day of vacation are not uncommon. Who will ever look at those?
Reducing those to the "best" 10-20 items already feels like an imposition to most. Reducing those further to 1 photograph to summarize the vacation is considered extremist by most. And even then, they will just mark the best photos, but won't delete anything except for the most blurred garbage photos.
Even more strangely, some people do feel the urge to clean up their mess, but as with physical items, deleting loads of digital items takes a lot of time for them. This is the next round of absurdity: They would rather spend a weekend (or full week) on finishing their photo/video archive than to go out for another trip.
Maybe we need a "digital item" version of Paul Graham's classic "stuff" article? http://paulgraham.com/stuff.html