I'm also 30+ and have a family, I simply do not have the time to code off-hours just to get a job

I'm not in this boat yet, but someday. One thing I think is important is to ask yourself, in all of computing, what is your favorite subject? Some examples might be: compilers, graphics, crypto, codecs, etc. Some people know a lot about a particular subject because they have a side project and they can tell you what are all the hard problems that might not be apparent to passers-by. Others with more experience have gotten that experience by working directly on such systems day to day. By having open source projects, it allows for an asynchronous review of your interests, your hopefully consistent use of style, what languages you work with, etc.

Let me try my hand at an anecdote.

Candidate A may have 15+ years of experience on many different subjects, but no open source projects to show.

Candidate B may have < 5 years of experience, but lots of open source projects.

Candidate A may have excellent knowledge about many subjects, but an interviewer probably wouldn't be able to asses the depth of knowledge as well unless they bring the candidate in for a technical interview. Without open source projects, that candidate may fall through the cracks and never get the chance for the face to face interview.

With candidate B, it can be immediately apparent for an interviewer to asses the candidates knowledge of version control, style, language, knowledge of workflow, etc, just by looking at their github.

The interviewer can learn much more about Candidate B than Candidate A before a face to face interview. My hypothesis, is that a strong open source portfolio is stronger than a strong resume before a face to face interview. If both candidates make it to a face to face interview, sure, B's experience may indeed earn them the role, but with just a paper resume and no code to show off, they may succumb to the interviewers bias' before getting to a face to face technical interview.

That being said, I'm super biased in favor of open source, and am curious to see how my outlook on this will shift as I get older. I do think the point that you made is important though, and it would me a lot to me and I would appreciate it if you or others could make that exact point here: https://github.com/nickdesaulniers/What-Open-Source-Means-To-Me