For "real-world" protests, I imagine that leaderless approach is a natural response to real threats to leaders. I think about a decade (1960s) that left nearly every one of its Black civil rights leaders dead by assassination, the FBI's COINTELPRO program, and local analogues like Portland's Secret Watchers program. Of course, places like Hong Kong, Nigeria, the West Bank etc. all have their own versions of these stories, but they are depressingly similar.
What are the origins and motivating factors for wiki and Wikipedia? I like to think that I know this history, but maybe there are pieces I have missed. I tend to think of it as an outgrowth of the free/open source software movement, that regarded corporate control of software as (for lack of a less dramatic word) tyrannical. I think the desire for more "free" places on the web stood in contrast to websites designed, archictected, sanitized, and optimized by corporate interests.
Founders and "leaders" in these spaces are important to think about in this context. See Leaders in "Leaderless" Spaces