I'm not trying to promote my cloud offering. I would like to be able to offer self hosting, but we still haven't found a way to do it. This is too much hassle for everyone. There is a tradeoff between ease of use of a software and the security process. A collaboration tool which is difficult to update and thus will not evolve quickly is an issue for its adoption and for its benefits.

Well first its interface, if a non technical user can't user the tool that's going to be a big problem. Confluence has not the best interface but still better than Xwiki. The best the interface the better the adoption as a whole in the company. And for knowledge sharing adoption is critical. That's actually why Notion has been such a success recently. Even though their product is average, people want to use it, because they like the interface.

I don't have the time to do a full comparaison of other features, but wiki tools are in usage very different than collaboration tools. Can you have the list of last consulted documents ? Can you embed external documents ? ... Kind of the same things as Slack vs IRC

Confluence can take text and turn it into a black box format shoved inside a database that you can't edit with a real editor, then shove that text into a black box unstandardized version control system shoved inside a database! Take that, other tools!