My play is I sell my advice and experience, and find companies willing to pay me to write open source software to meet their needs.
I have built a security firm that only audits code/ architecture and writes open source code and it can generate enough income to support a few people in a way I feel good about.
I try to put people before profit and that is probably why I am not cut out to be a billionaire.
TLDR: FOSS devs still need to eat, so we'd better come up with a sustainable biz model, so we can keep working on FOSS.