I've used 'Wikis' since "WikiWiki" was an unknown term. It's not just Confluence, it's a human behavior problem.
This is a generic problem with any system with zero curation and bad search. Information is out there, but you've no idea if what you're looking at is valid.
First, accept that basically anything else is worse. I'll never use Sharepoint again willingly.
That being said, there are some things you can do with your Wiki operations that make things better:
The above basically encourage people to keep pages up-to-date. You're fighting human behavior, not any particular problem with Wiki/Confluence.
We're a place where coders share, stay up-to-date and grow their careers.
We strive for transparency and don't collect excess data.