The OP uses the word "insane", not outlier. It's clickbaity, and used in jest, but I think it better captures a subtlety of this phenomenon: The prolific commenters are molding every discussion in their image. They might have an interesting angle on the story, or they might just be saying trivial things with beautiful prose. In any case, there is a lack of diversity in general -- discussions are driven by the worldview of a few.
That would be an argument for lurkers to make an effort, even if, like this comment, it's just a barely-formed idea.
Edit: "molding the discussion" -> "molding every discussion"
The point is: the hurdle to contribute or even create is quite high, no matter if it's on the internet or in the "real world".
Stackoverflow is not a magic community, they have guidelines otherwise their content won't work so well. Same goes for Wikipedia. As a matter of fact, either you know how these sites work and what is expected or your content gets downvoted and eventually removed. Even HN works like this.
So yes, then there is a small percentage of users that took the hurdle to internalize how things work. It's much easier actually when you do it regularly. In fact I used to be Wikipedia contributor but I gave it up because it's time consuming and frustrating. If you're not a frequent user, you can correct orthographic errors, anything else is pointless unless you're a writing genius/journalist.
Nobody ever complains how insane they are working 10+ hours a day for an unstable job and oftentimes bad salary.