The 2024 Tidelift state of the open source maintainer report (https://explore.tidelift.com/2024-survey) disagrees. And that is probably the most comprehensive one that actually favors large projects, because of Tidelift business model.

> The portion of respondents who reported they are unpaid hobbyists remains at 60 percent, the same as in last year's survey.

Only 12% checked "I'm a semi-professional maintainer, and earn most of my income from maintaining projects." 24% checked "some of my income from maintaining projects"

I don't think so. If you're saying that in big projects (e.g. Linux) most developers are paid, sure, but those projects are a drop in the ocean of open source projects. I doubt very much that there are more paid than unpaid OSS developers but neither of us are bringing numbers.

Open source isn't charity - just like playing non-professional sports isn't charity: the vast majority of participants see it as a hobby or social activity. A minority get paid, and a minority of the minority "break even", but vast majority are playing in self-organized leagues and pick up games, which are in no shape or form charities (even if the public can watch for free as a side-effect).