Dropbox on iPhone hasn't synced in a year. I've tried everything.

Hey kazuhaga​, thanks for the info!

Now let's address everything. 😊 The first thing I need to mention is that your Library folder on your Mac should be hidden by default. Also, while we're working to resolve this please hold back from creating any folders in order to move the Dropbox folder in which you can see your files. 

One small clarification: if you access this path Users/kazuhaga/Library/CloudStorage/Dropbox can you see your content there, or does it look empty? I'm asking because your screenshot from earlier showed a blank Dropbox back.

Also, it looks like you're using Dropbox on File Provider, hence the folder path /CloudStorage.

Here's my suggestion: please create a test folder online, and give it a random name that doesn't exist locally. If the app's syncing status is up-to-date then you should see the file locally. Feel free to search in Finder for your test folder, and let me know what you find. 

If the above doesn't work, and you have trouble locating your online files please try signing out and back into the app.