There is a small group of core "editors". I am not aware of the dynamics within that group, but obviously it is sanctioned and directed by the Wikimedia foundat

There is a small group of core "editors". I am not aware of the dynamics within that group, but obviously it is sanctioned and directed by the Wikimedia foundation (certainly through setting policy and allocating budget, but likely also through other forms of direction and interaction). This sets the historical, political and ontological outlook of Wikipedia, in very broad strokes; and decides the actual content on a huge number of articles. Of course, lay "editors" contribute a huge amount of text, but that's not the "driving" part.