An important aspect of the success of D&D/40k has been fan creations and lore explainers. A challenge for growing a creative commons (alternatives is that there isn't a unified set of "cannon" stories for independent creators to make "TOP 10 WACKIEST THINGS IN [franchise]" which are the intellectual equivalent to baby food (which I don't mean as an insult).

then again, d&d and 40k are popular because the companies that own them decided to let smaller creators do the work of reprocessing the decades worth of lore into easily consumable and marketable chunks. Both the small creators and the central company got to symbiotically feed off of the brand value of the other. Then begins the enshitification once the brand reaches the mainstream

The problem for less centrally controlled media isn't just that there isn't decades worth interconnected lore within one overarching franchise, it's that stories that aren't centrally controlled will mutate and be remixed too much to have the sort of symbiotic brand growth of 40k and d&d

Yeah, this is very complex idea and also at the same time, I think IF open source community can handle or focus on privacy and security to the max that even Quantum Encryption can't break it (again, from our community first rather than come from military standard or big corporations), we can create FOSSicon Valley in reality. Of course there's a pros and cons bout this, but I think if we think about it together, then the problem would be solved by the nature of open source itself. This is imho from optimistic POV for this topic..

Interesting that you mention open souce shared universes. I mean, at the end of the day, all of these become public domain anyways. The problem is that it takes way too long.

But for example with "lord of the rings", it will someday be available to the public and then things will get interesting, especially with AI these days ...

However, I think people should experiment with what I call “open source universes”, which is basically creating shared universes that are open source. Maybe even make some open source RPG system with it too, so we could have an open source alternative to the likes of D&D, WH40k, etc. At one point I tried to make something like this, but the issue was that it was based on an old webcomic idea of mine, which I started working on when I had totally different views on many things. Might revisit it with different ideas later on.

Haven't played any of those, but I think they (and more) exist for a long time already: https://wiki.rpg.net/index.php/Open_Game_Systems