I think Barthes's Death of the author pretty much destroys the idea of cannon at all - so the question "is it art?" is irrelevant. It both is, and is not art, at the same time. It's how you choose to interprit it that's important.
The author of the article here uses Barthes, but then ignores him, becuase Blow's voice is too omnipresent. He wants to deconstruct the game to find his meaning, but is distracted by trying to find the difference between the character's voice and Blow's voice - both in the game and online.
There is no One True Meaning - you can only pull each thread of narrative as you find them attractive and see where it leads, using your own experiences to make connections with other works of art, or other moments in your existence.
The moment anything is created, the author loses control over it - they cannot choose how anyone will interprit anything, as they are different from you.