I'm completely comfortable with a "if no one's making it available reasonably, it should be made so" policy. I'm only concerned for living creators to retain rights to their work and be compensated for their creations while they are still actively using their work to give themselves a living, so I would be fine with ensuring work isn't irrevocably lost due to lack of copies.

I think the other side of copyrights where you can irrevocably sign over your rights (which may be more of a US thing, UK seems to have some inalienable ones) is a significant issue (as mentioned, the Foster thing where Disney wasn't even paying him because they argued they'd acquired assets without liabilities - https://winteriscoming.net/2021/04/23/disney-star-wars-autho... ).

It's hard to fully balance. Another example would be Don Rosa's McDuck comics - he had to fully assign all copyright on them to Disney when making them, so the way the reprinters get him some money is by having him write forwards/commentary, those he can retain the copyright on - https://career-end.donrosa.de has more

Alan Dean Foster's situation was not an irrevocably signing over his rights; he signed a specific business agreement that Disney tried to renege on dubious claims that would totally change corporate law if it was made valid precedent.

Don Rosa's situation doesn't really have much to do with the original advocacy to do away with copyright altogether, so I don't understand your point here. Are you arguing that copyright is bad because it's sellable under unfair terms, and therefore no one should be able to sell their work?

I'm just pointing out that our current system of copyright doesn't really do enough to protect the authors and artists that create the works we enjoy; there's certainly room for improvement.