So, we're going to have to throw stuff away. Even if we believe keeping stuff is really cheap, its still too expensive. The bad news is that deciding what to keep and what to throw away isn't free either.
This is so very true.
When my team inherited the responsibility for Archival Storage at ICPSR in 2005-2006, we made a choice to throw away a ton of stuff. Paper hardcopies of electronic files. Magnetic tapes that had been read successfully to spinning disk. Old office supplies. Leases to storage lockers. .... After the smoke cleared we had about 5TB of content moved from a large array of tape types to spinning disk. And this formed the core of ICPSR's Archival Storage.
I think a key question for every archive to answer is "Why are we keeping this?"
If the answer is "We're not sure" (even with some oblique wording), then it is time for that item to be discarded.