The tooltip says: "When set, users see the contents of /homes, which includes the home directories of other users. When unset, users only see their own home directory."
Based on this description, I turned it off, because I don't have/want any network homes, and even if I did I'd only want each user to see his own. But I do want network shares. It seems without this checkbox turned on, the share cannot be connected to at all (at least from macOS). Took me a while it figure that out!
It's almost as if the checkbox title makes sense, and the tooltip is totally wrong or copy-pasted from something else...