Right now, I am struggling because of unemployment and job shortage in the tech-market, but I'm planning to share my own patches to essential software, like you've mentioned - probably within the end of this month. I think projects like Node, Ruby and Python need to be maintained well enough.
So if I have a chance to, I'll probably work on either one of them, especially Node - that seems to be quite dated, and they've also skipped on v16, which hurts people who are still on it and don't want to migrate immediately - because there's no inferiors to pin to - while there's multiple commits at least for 10, 14 and 18. Working on it would make Guix convincing as a third-party system package manager. I don't know the state of Ruby or Python, but Zig seems to be in a decently good condition. Rust may be removed probably to avoid trademark violations, or they'll probably create a fork and rename it.
About the FOSS extremism, it is not that bad, and I honestly like it the way they've maintained it - in a way, it is very similar to how Fedora separates their free and non-free repositories. This is not to say that there's provisions for no non-free drivers - in fact, I personally use them for my Wi-Fi drivers to work correctly. Given the state of FLOSS-respecting Wi-Fi hardware, Wi-Fi 5 devices still don't have their respective open-source drivers, so 6, 6E and 7 are still going to be unsupported for a long time with the libre kernel. For folks who want to setup a working system easily, nonguix ISOs are readily available, so that would probably be the best place for anyone to start at.