No matter what I’ve tried, nothing beats google docs for me (in a mixed discipline work environment). It has the familiarity of a folder structure, good collaboration features and version history that works well for non technical users. It works well enough that few users fall back on v2_final-edit naming nonsense. Other tools have a slight edge for organizing information, but no good way to keep both files and Documents together. Which means people use files locally and don’t keep them up to date on the system.
It had 3 pain points for me that are resolved recently. First, they got rid of the desktop clients so users can’t move stuff to their desktop without understanding this is removing files for others. Second, team drives resolve the mess that was shared folders. Third, it can now edit office documents directly, avoiding the confusion of google doc copies appearing.
I use confluence a lot and I never trust that files on it are up to date. It doesn’t quite have enough features to make “native” documents, so it ends up with a lot of content stored as attachments, which inevitably get updated and passed around by email. It’s not convenient for storing files so all of the miscellaneous small files never make it there. If you use a lot of addins, it becomes usable to make documents but since it’s atrocious at outputting files, eventually a final version of something needs to be edited in word and now it’s even worse, you have what looks like an up to date document but the latest version is a word file, which is either hidden as an attachment or not even uploaded. I can see it working well in a team of only software engineers, however.