Issue: Can't seem to disable discussions completely...

The wiki lets you post about the wiki page you're reading without leaving and having to open a thread in a separate sub-forum. That's all.

Even if you don't have permissions to post or add new discussions, you can still read ones that are already there, and if they are turned on it would still tell you there are no new posts. You can remove the discussions feature entirely for each area by modifying the settings for that area. There's a setting for what kinds of discussions are allowed.

I'm not sure how it works if there are already discussions and you disable them after. In that case it might still show them but you wouldn't be able to add to it.