If you want to improve on the wild-and-easy stage of everyone just using the wiki however they feel like, just have some rules.
For devops work, have a page for all your objects. Track lifetime events (the non-automatic kind) there. Swapped yet another disk in machine b47f8? You'll see the record in the wiki and can maybe also swap the controller or cables. Looking for the local installation procedure of some software? look at the wiki page. Doing another installation on a different host group? put a link in the wiki from hostgroup to software and vice versa. Have page templates for all objects and tasks.
The trick is "no change without wiki change". "No identical second support answer without wiki FAQ entry". The trick is documentation discipline.
(I know that some tasks may be better served with e.g. proper inventory software, however, there is something to be said for everything documentation-like in one place).
Oh, and ffs, never delete history, it will definitely bite you someday.
It strikes me that all the various "corporate wiki" services are really just trying to patch over the absence of staff dedicated to this role.
Yes but this is not the biggest issue. The biggest issue is the culture. In the short term it is easier to not have a proper documentation, so if you don't have an enforced culture about written documentation, this will always be an issue
IMO, the tools themselves are really failing us here.
I'm creating a new document? Give me some kind of super-powered organizer algorithm. Auto-suggest the appropriate tags & folder/space location based on the content.
I'm an admin and trying to clean up the clutter? Run that same algorithm across the entire space and auto-suggest a better layout & document naming. Make it easy to bulk move/delete documents, folders, etc. Surface old, unvisited documents with no edits & recommend for archiving.
Search indexes could also take into account age of the document, # of edits, # of days _since_ an edit, etc.
I could go on.