scaling with market cap and having a huge “free” tier is an interesting approach. Something like an official license requiring companies to pay 10k for each trillion $ market cap calculated on jan first of the current year

low complexity, low decision making overhead. it wouldn’t help for small or very specialized open source projects but the big ones that keep the world running are probably used in some way in all the big companies anyways so the total should come out somewhere in the range of 1-2 developer salaries (adjust the 10k above to match. no idea how many trillion+ companies there are right now)

edit: I overestimated how many there are. With 10k one would get to 50k this year. Numbers must be adjusted a bit :)