[Delurking to ask a question that might be illuminating]
Can I use this thread to ask a question as a "worked example"? *Procedurally*, what was the way in which "nofollow" was added to external links? My impression was that Wales just said to do it, and it was done, even though there was no "community consensus". Now, I'm not saying it was the wrong thing to do. But from an outsider's perspective, it was pretty much an instance of "He's the decider".
FYI, to dispose of a myth, there was no SEO contest targeting Wikipedia. The SEO contest in the news had specifically ruled out such "black hat" tactics, and would have disqualified anyone caught using them.
Much of the talk of Wikipedia's governance tends to be along the lines of "How many divisions does the Pope have?". It's true that the Pope is the Pope only and solely because many people believe in him and trust him. And a dissatisfied group could break off and decide they want a new Pope, or no Pope at all. It's happened before in history. But that all sort of misses the point. ALL governance, by definition, is a social construct, which works only because enough people believe in it. The deeper questions are what benefits there are to believing in it, and what sanctions can be imposed for not believing in it.