those are artifacts of digital culture worth preserving, and the source code for some of these could be interesting.
Exactly my take on it. You never know if a particular program was available from more than one collection or not until you've been able to see the program and compare it with other collections. (Just looking at the filename isn't enough: how many different people had their own ideas on what BEEP.COM should do?) After all, not every program was "popular enough" to make it into Simtel. Also, older programs would get culled out of collections like Simtel to make room for "newer and better" programs that did the same thing. Some programs were culled just because their function was no longer necessary on newer hardware or DOS versions.
Luckily for all of us here, the bulk of PC-SIGs collection made it to CD-ROM and therefore got preserved. Those programs that weren't on CD-ROM likely exist in other surviving collections, but we might never be certain that there wasn't something on these disks that didn't get copied over.
There's also the problem of missing particular revisions in the version history of a program. For example, this person's research of 4DOS's history:
https://4dos.info/v4dos.htm
When a new version came out many of these groups replaced the old version with the new one making the tracking of developments harder.
PBS was the largest distributor of PC shareware back in the early 90s; it was sold to Ziff-Davis for inclusion into CompuServe's file offerings sometime around 1991.
Interesting, I had heard it was PSL [the Public (software) Library] that was the largest distributor. I wonder when PBS took the lead. Regardless, both of them were major distributors and neither of their collections survive mainly intact. I still have seen references in books and magazine articles to some programs you could get by requesting PSL disk #xxx or contacting Public Brand Software. Anyone seeing these references today is left out, not able to try the programs for themselves.
Is there any backup of CompuServe's file library anywhere?
Now there's another large collection that would be great to have access to. I know some things were only available on Compuserve because their authors made them Compuserve exclusives.
I've never seen any backup of the file library. So I also want to know if anyone has found one.