Adding support for larger maps and colored lightmaps, for example. Quake still has an active modding community, and many of the most impressive maps require a source port with increased engine limits. The original engine just can't handle their scale and complexity.
Luckily your tokens are equally accepted as legal tender to the code machine, so if you want it, you can have it.
It a new world. You can literally maintain your own fork with the features you want.
Even the AI models are not gate-kept, soon. In 2030 you'll be able to affordably buy a GPU that can run an open weight model equal to the best that 2026 had to offer. I.e. projects like this.