I do agree that the tagging is useful as a sort of record to find things in the journal but I think it still can be done even if the game does change to comm based?

For example, say you're making a post to the comm. You can just mirror/crosspost that in your journal. On your journal you create your own tags like you said and the comments section on your journal entry you can just link to the comm entry? ...Hopefully that makes sense.