It goes far beyond the actual codebase to the long tail of supporting projects, conference talks, blog posts, etc

Agree. Writing code is (TBH, only a tiny) part of the project - creating packages for different OSes and distros, testing, filling bug reports, promoting project, writing tips and ticks, articles... Many projects remain unpopular not because the authors aren’t actively maintaining them but because these essential components are missing.

As one of those 12 other people, number of commits is not a good metric in this context. When you have a single maintainer, like antirez was for a long time, he could commit 10+ commits for a single small feature but I needed to get someone else to approve my commit before merging.