It's one thing that copyright/IP is such a matter of debate in the creative world, but a whole new layer is added onto that when people say that it only matters for a certain amount of time. You may have read all those articles a few months ago, the same ones telling us about how Mickey Mouse (technically Steamboat Willy) is now up for grabs 95 years after his creation.
There are those who say "as long as it's popular it shouldn't be pirated", those who say "as long as the creator is around", those who don't apply a set frame, etc. I've even seen people say they wouldn't dare redistribute paleolithic paintings because it was their spark on the world. What philosophy of statutes of limitation make the most sense to you when it comes to creative work?
I'm in favor of abolishing IP altogether, along with all Private Property.
I support complete abolition of intellectual property as a whole.
Say you want to write closed captions for a movie, or even film a sign language interpretation of it, such that d/Deaf people can enjoy the movie better, among other reasons — even if you don't post the movie itself, you're still creating a derivative work and hence violating copyright.
Or say you want to record an audio description such that blind people can enjoy the movie better, among other reasons — again, even if you release only the AD track, this is still a derivative work and hence violates copyright. This obviously also goes for audiobooks.
Or say you even want to make a full-on dub of a movie into an endangered language, to try to break the reliance of its dwindling speakers on dominant-language content — in this case, unless you've secured a deal with the rightsholders such that you have access to the original SFX and music tracks, your only choices are VO dubbing like is common in the Former Soviet Union, or painstakingly redoing all the sound effects and music, before you can add the dialog. In any case, without a license, you're still violating copyright even if you only release the dub track.
Now obviously the fact that these things violate IPR doesn't stop people from making these things anyways, but IPR does still end up greatly limiting volunteer work in scope and visibility, and creates an antagonism between the rightsholders and those volunteering to make the content more accessible. So intellectual property in practice then ends up being among other things yet another mechanism through which the sighted oppress the blind, the hearing oppress the d/Deaf, the settlers oppress the Natives, et cetera. There is no universe in which accessible media and intellectual property coexist: as long as there is intellectual property there is a profit motive, and profit motives will never prioritize accessibility.
And this is not to get into a greater discussion of how private property in general oppresses the working class, although I should disclose that I support the abolition of all private property and not only intellectual property by itself.
Granted it's an honorability rather than abstinence thing, but why expire it?
Frankly, if you're a small creator, copyright already doesn't really exist for you in any meaningful sense: because copyright is enforced through the courts, you only really have rights over your work to the extent you can actually pay the court costs of continually defending your rights again and again and again — and if you have that kind of money to spare you aren't exactly a starving artist.
This is going to sound really tedious, but what I'm trying to get at is this:
To justify that "no more or less than the author's lifetime" is the perfect length of time for copyright to last, you must at the same time justify that "more or less than the author's lifetime" is not the perfect length of time for copyright to last.
The time limitations of "0 seconds" and "until the heat death of the universe" are more and less than the author's lifetime, which means that you must justify why these are not the perfect length of time for copyright, just the same as any finite time limitation.
In other words, in order to justify that the author's lifetime is the perfect length of time for copyright to last, you must first justify both that copyright exists and that it expires. Hence, "What do you think the purpose of copyright is?"
It's from the answer to that question that you come up with criteria to judge time limitations, and it is from those criteria that you decide on an ideal time limitation. On the other hand, without an answer to that question, your beliefs have no actual basis beyond gut feeling.
Likewise, to criticize someone's understanding of the purpose or nature of copyright, is criticizing the criteria used for finding an ideal time limitation, is criticizing the favored time limitation itself. My first reply was then based on an assumption of what I figured you thought the purpose of copyright was.
IMO it is a matter of who wants to use said copyrighted material, for what purpose, and to what end. And not necessarily over some period of time. Two licenses I use.
GNU Public License version 3, GPLv3. Strong copyleft. The right to copy is left to the end user. You can do whatever the hell you want with the code provided you pay forward the four basic freedoms granted to you under the license. I.e. You can view the source code, you can modify the source code, you can distribute the source code, and you can distribute your modifications.
If you do not pay forward the four basic freedoms, you are in violation of the license. This is why google, microsoft, etc. WILL NOT use gplv3 code. They will never grant the four freedoms downstream, and they don't need the legal liability. They have code scanners that look for gplv3 code, and as a developer you use it, they will fire you on the spot. Serious shit.
The second is Creative Commons, CC. There are several variations based on if you can create derivative work, if you can make money off of it, if you need to credit upstream contributors. The one I use is CC-BY-NC-SA. That's you can create derivative works and distribute them provided you: attribute pervious authors i.e. who is it BY, you can't sell it i.e. it is Non Commercial, and since this was shared with you, you must Share Alike.
All that said, these are in a different category than commercial licenses, so restrictions may apply.
Also. "Intellectual property" is bullshit. It's incredibly ambigous and doesn't hold legal value itself. There are three things that do. Copyright, patent, and trademark. Each wrought with their own issues, but the broad concept of intellectual property only exists soley exploit those who don't know better.