I think it would be reasonable to establish a bar, similar to offline where everything above it is archived, and everything below is optional opt-in.
In the offline world the National Libraries get a copy of every book, magazine and newspaper published, by law. At least that's the way the UK and US do it. They archive a lot of other stuff as well, including music, audio, adverts, but that's more informal, and there is no requirement to preserve.
Personally I'd like things politicians and personalities (by dint of having chosen to live large) say online archived, all business (to later hold them to account) along with the sites of anyone in the business of influence - think tanks, parties, lobbyists, activists, "grass roots" organisations etc. Individuals, anon forums, HN and reddit subs and other places of shooting the breeze should be allowed to stay ephemeral. In fact I think conversation is freer that way - some will choose to say less, say different, or say nothing if all everyone says is forever...
In the US, mandatory deposit technically applies to any copyrighted work of any kind. We should fund LoC to enforce mandatory deposit on digitally published works as well.
In a sense this is also a good demarcation point. If something is serious enough to be worthy of copyright protection, it's probably worth archiving.
Funny you mention HN and Reddit as ephemeral because I always thought they were more permanent than most. While you can email the mods and ask that a particular post of yours be removed, I don’t think they will wholesale scrub your content out of the archives if you request, or help to anonymize them in any way.
I consider HN pretty much permanent and tread carefully with controversial opinions or things that might one day be considered not-PC.
What law in The US? In ancient times, like 40+ yrs ago, before the first big extension / copyright automatically granted at moment of creation. It used to be req to send copy to LoC to earn right to enforce copyright.
I've published several books the LoC does not have.
Also the national libraries aren't the sole archives of culture. Univ and private libs preserve all the important stuff government has not the interest or budget for.
To my surprise, I learned a few months back that mandatory deposit [1] is still actually a thing, albeit a completely unenforced thing. (I believe deposit is needed if you want to sue for damages, but in theory you're supposed to deposit in any case.)
In the offline world the National Libraries get a copy of every book, magazine and newspaper published, by law. At least that's the way the UK and US do it. They archive a lot of other stuff as well, including music, audio, adverts, but that's more informal, and there is no requirement to preserve.
Personally I'd like things politicians and personalities (by dint of having chosen to live large) say online archived, all business (to later hold them to account) along with the sites of anyone in the business of influence - think tanks, parties, lobbyists, activists, "grass roots" organisations etc. Individuals, anon forums, HN and reddit subs and other places of shooting the breeze should be allowed to stay ephemeral. In fact I think conversation is freer that way - some will choose to say less, say different, or say nothing if all everyone says is forever...