> I'd argue that software, and in particular operating-system software is perhaps one of the most predictable categories. It inherently ages due to gradual drift on hardware support and growing burdens of security risks and unmet compatibility needs. A 20-year-old operating system is probably only interesting for academic, historic/nostalgic, or special-case legacy support reasons.

Windows XP has only “aged” because Microsoft made a marketing decision to make it seem as though it has aged. Windows XP likely shares millions of lines of code with Windows 10. They only have the appearance of being a different product for marketing purposes. As a copy protected work, one is a direct derivative of the other. This type of life expectancy cannot be predicted.

Good policy is generically applied, fair, and sound. Saying “well operating systems should not have the same copy protections as other works for xyz reason” isn’t effective policy and would likely be found self-contradictory in court.

> I don't think you can draw conclusions from the behaviour of lawmakers, who are likely easily swayed by existing stakeholders who have a financial stake in expanded copyright.

Why not? What is the other side of the coin? The people arguing for decreased protection are doing it with no intention of starting businesses. They are ideologically motivated, not pragmatically. They simply want a world where they can do whatever they want with anyone’s IP because they think that’s how the world should work in the abstract, not because they intend to produce anything of sustainable value. Most of these detractors want to create one-off art pieces for the fun of it. That doesn’t bring food to the table or build a long term foundation upon which more advanced works be built.

The people arguing for more copyright protection do it with the intention of continuing to build more sustainable value. This results in more jobs and a larger economy.

> pieces of a shared zeitgeist that happens to be privately owned.

Chance has very little to do with it. We used Windows XP because Microsoft spent billions in marketing to distribute it and grow the PC market. It didn’t just happen by accident. Look at all the other fully functional hobby OSes that exist today. Look at ReactOS. Look at Linux. It’s not an accident that they don’t have the market share that Microsoft does. They don’t have an institution that is properly incentivized to market them to the masses. The most well known and used alternative OSes are Fedora and Ubuntu, can you guess why? It’s not random.