"In a typical year the OpenSSL project receives about US$2000 in donations."
OpenSSL is one of the most known open source projects. It's like https://xkcd.com/2347/ There's little hope to achieve its level of success by doing open source. And even that project did not earn good money. So living from open source project just by writing code just is not a good idea. It's possible to run open source project as part of startup, I guess. But that's more about marketing than writing code.
"In a typical year the OpenSSL project receives about US$2000 in donations."
OpenSSL is one of the most known open source projects. It's like https://xkcd.com/2347/ There's little hope to achieve its level of success by doing open source. And even that project did not earn good money. So living from open source project just by writing code just is not a good idea. It's possible to run open source project as part of startup, I guess. But that's more about marketing than writing code.