I also use org-mode as a personal wiki, combined with git version control and ripgrep search. Furthermore, my task/time management is also within the wiki, as a kanban page and as an events page. Org has tons of useful features. Especially for time management and export. But it's also quite simple.

I started implementing a personal wiki using MediaWiki long time ago, trying to replicate the concept of Zettelkasten. But MediaWiki is a bit too heavy and complex, even if you use a SQLite backend. Furthermore, it doesn't compose with my editor and version control system of choice.

I think having a wiki is essential, as the deliverable of many tasks is just a knowledge bit you really want to record. It's interesting to see personal wikis are starting to show up in GitHub and GitLab. I wish both platforms improved their org-mode support to capitalize on this trend. We can all collectively benefit from open-sourced wikis in the same way we benefit from open code.