Ireland recently created a Basic Income scheme for artists.
Europe should have an equivalent scheme for programmers of important Open Source projects such as this one.
The problem was more than remuneration. It was burnout and mental health issues. They may have been moderated by income but we don’t know.
Also today as I understand it much of OSS is done in-house by major companies (red hat, Ubuntu, ibm, Google, etc)
Just German, not European, but still a start: https://en.wikipedia.org/wiki/Sovereign_Tech_Agency