I doubt it, but that's just a hunch. Is there data out there regarding compiler/language maintainer/standards committee members' contributions to other projects

I doubt it, but that's just a hunch. Is there data out there regarding compiler/language maintainer/standards committee members' contributions to other projects (beyond "so and so person works on $compiler and $application, both written in C"-type anecdotes)? If not, then, like ... sure, C compiler maintainers people who program in C, but they're not "C programmers" as it was intended (people who develop non-compiler software in C). My hunch is that that statement is overwhelmingly true if measured by influence of a given C compiler/implementation stack (because GCC/LLVM/MSVC take up a huge slice of the market, and their maintainers are in many cases paid specialists who don't do significant work on other projects), but untrue if measured by count of people who have worked on C compilers (because there are a huge number of small-market-share/niche compilers out there, often maintained by groups who develop those compilers for a specific, often closed-source, platform/SoC/whatever).