The last paragraph of the article seems to equate "a game that's meant to be played" with "real sandbox simulation, autonomous agents and language-capable AI", and that seems like a narrow idea of what "playing" means, one which equates interactivity (which is the distinguishing feature of games) with choice or nonlinearity. Providing players with lasting choices is one way in which you can use interactivity to structure an experience, but it's not the only one. There's some interesting comments on this in a review by Emily Short of the IF game "Howling Dogs": http://emshort.wordpress.com/2012/10/10/if-comp-2012-howling...
"Howling Dogs" is something of a masterclass in the different ways games can use interaction, and I'd recommend people check it out as a supplement to the vision of gaming put forward in this article.