I think there is enough tasks to warrant this tag. If that is not the case feel free to decline this. I just figured it may be a good idea, but that's just a personal opinion.
A few examples of tasks that may fall under this:
T6977: Document Memcached
T6978: Document the MediaWiki Application Stack
T7214: Write docs for GHSA
T8070: Update docs for new deploy system
T8843: Implement documentation for all monitoring checks
T8847: Icinga docs entries for all Infrastructure monitoring
T8848: Icinga docs entries for all MediaWiki monitoring