C++ language evolution is developed mostly in public. We don't get to see WG21 meetings, but we see most of the emails (https://lists.isocpp.org/std-proposals/

C++ language evolution is developed mostly in public. We don't get to see WG21 meetings, but we see most of the emails (https://lists.isocpp.org/std-proposals/ https://lists.isocpp.org/std-proposals/), almost all of the TS proposal papers (everything except for very early drafts), and notable meetings still have multiple recaps from various participants in addition the the Meeting Minutes publicly outlining what these discussions are about, and we see (afaik) all of the formal votes that the committee members take (although the votes are anonymized). Plus a considerable amount of the conversation happens on GitHub, and many paper authors ask for feedback on Reddit and chat clients. Also, the standards work is only a portion of C++ language evolution. Clang RFCs are public and anyone can provide feedback, the GCC mailing list is public, and both of their issue trackers (which include feature requests) are public.