I think part of the ArchWiki’s strength is that it treats documentation as first-class infrastructure. There is a shared expectation that if you solve something nontrivial, you upstream it into the wiki in a reasonably neutral, upstream-oriented way. That creates compounding returns over time. It also helps that Arch has a relatively coherent user base with similar assumptions about init systems, packaging, and defaults.

Many other distributions fragment their knowledge across mailing lists, forum posts, bug trackers, and random blog entries. That worked when search engines were good at surfacing niche technical content. With current search quality, especially the SEO noise layer, the absence of a canonical, well-curated wiki becomes very visible.