You seem to imply that there is consensus finding among groups of coders, but is that really what happens? Most of the time, at least from my perspective, it is simply a single dev (or rarely two or three) doing their thing. Sometimes that work is picked up by others. Most of the time, it isn't.
There is barely any consensus finding of larger groups at all. Consequently, there have been almost no advances which required wider consensus over the last months/years.