Essentially I treat the wiki like a B-Tree. When the landing page gets crowded, I move a bunch of related things down one level in the hierarchy, trying to retain keystone ideas within the first to levels (and letting related concepts be discoverable from those).
Over time the oldest links and links of only temporary utility get pushed out to the leaf nodes, where you aren’t likely to encounter them accidentally.
Really, though, we should be applying the same sort of version control we have in our source code. You should be able to track down how old a paragraph is in the wiki.
We also evaluated Confluence with this https://marketplace.atlassian.com/apps/123/better-content-ar... but if the concept is not a first class citizen in the wiki, it does not work as well.
I tried to convince the people at Clubhouse (with their Write app in beta) and Notion, but I don't think they get it.
I experienced this in the wiki/documentation space some years ago when my org migrated from the trac wiki to Confluence. It seemed like such a boost initially, but it wasn't a boost at all, it was just the fact that for the first ~12 months after migrating, you could trust that everything you found in the wiki was freshly written and up to date (and the overall corpus was small enough that the search function actually returned useful results).
The whole experience has given me the idea of making a Confluence plugin that slowly fades out each page to grey as a visual indication of its waning relevance. Anyone editing, commenting, or "liking" the page immediately freshens it again, unless they somehow indicate that the action is actually a vote against (like nofollow is for links). When a page is sufficiently abandoned, it goes on a candidate-for-deletion list, gets a warning box at the top, and is blacklisted from appearing in the default search results.