"The optimum population piece was published in one of Julian Simon's books, and he, unfortunately, is no longer alive, so I don't know how I would get permission to web it."

https://plus.google.com/117663015413546257905/posts/fsYycWa8...

This suggests a few things to me (a lack of clarity on the part of an author over rights to his own works, a surprising lack of knowledge of copyright or rights management, generally, etc.). But it's a quite tangible instance of an author of a work stymied by the question of copyright status due to the death of a publisher / editor.

Wrong. The DMCA provides safe harbor for online service providers. It provides no safe harbor for those who personally reproduce a copyrighted work, on an online service or otherwise. Rather, it increases the penalties if such reproduction is infringing. And I don't see how David Friedman is under any obligation to take such a risk or research the status of a work to which he owns no rights, did not author, and does not benefit from.

To paraphrase a comment I made on an earlier HN thread about copyright:

Consider a short story published in a literary journal last week. Allow a copyright system to exist that covers each eligible work for 30 years by default, and allows multiple extensions of 5 years at a cost of $1000 per extension per work, up to a maximum total copyright term of 100 years.

Someone in 2047 discovers a copy of this particular journal issue, which has now become obscure. They identify that this short story, though never being given acclaim, has had a subtle yet profound cultural influence. They decide to republish the story in their own commercial magazine, but want to check if the copyright has been extended. If it has not, the story is in the public domain. If is has been extended, the story is still covered by copyright.

They can search the central registry for the title of the short story and the name of the author. But they also have to search for the names of the editors of the journal, because it isn't clear whether or not the copyright stayed with the author or was transferred to the journal as part of the submission process. In fact, the copyright might have been granted to the owner of the journal, which may be an individual or may be an institution. The entry for the copyright might be under the title of the short story, or under the title for the journal, or under the title of that particular issue of the journal. Furthermore, the author of the story, if they retained the copyright, may have submitted the story under a pen name, and/or may have registered the copyright of the short story under a different title than the title they used to submit to the journal, or the title might have been changed by the editors. Or, the author, after having the short story accepted by the journal, may have sold it to a publisher who published it in a short fiction anthology, the copyright for which is registered completely separately and is essentially invisible to our hypothetical future researcher.

Any of these agents might have extended the copyright. It would be extremely difficult to prove to a high degree of certainty that the story was or was not covered by copyright.

Isn't that going to become less of a concern as most content and creators are very public online these days?

I think you are experiencing a bit of sampling/availability bias. Sometimes the most obscure works are the most interesting.