Hi Ian.
It seems like you care a lot about this topic, and have a lot of feelings about it. I think it's great that you're interrogating the terminology, because it can be confusing to people who aren't familiar with it. But I'm not sure that the OP said or implied that everyone needs to use narrative conventions when telling stories together. It seems like you're reading a lot Sandy Pug Games' post. I can totally understand how that is! But I think in this case you're reading something that is not there. Sandy Pug Games, and the people replying to you, aren't saying that WotC has to put these concepts in their text. They're not saying that everyone has to care about the concepts. It seems like they're saying that it is okay to care about these concepts, and that they can have a benefit in some cases.
Does my assessment seem fair, or am I off in some regard? I would be happy to hear what I've missed in the discussion.