That very same people that you say can't imagine anything "beyond a game in it's most primitive, literal form" are proof of this phenomena. There is a thing such as "two different conceptions, and comments like the one we have seen here are proof of that; it is observable. I would say that what doesn't exist is not "two conceptions", but two concepts. A concept, of course, makes the mind instantly think of structures and specifiicity, that is why I used "conceptions", to be a little more vague, because, of course, attempting to put every possible manifestation of videogames into two bags it's restrictive.
That being said, it's impossible not to notice some kind of divide. The very fact that the syntagma "indie game" exists, implies the logical fact that there is such a thing as "indie games" and, on the other side, "not-indie games". I don't, obviously, identify either one with a more "discursive" aspect just like that, but I think that indie games tend to gravitate towards that notions even more (with that I mean, a stronger emphasis on a given concept, a discourse, than on any other possible element).
My idea, simply put, is that people that make indie games generally try to make games that means something, that reveal aspects of ourselves (the subject) and the world that makes both feel renewed. I'm not trying to diminish any possible manifestation of art in videogames; i'm simply celebrating all of it's vast array of posibilities (triple A games of course can also do that, but I don't think it's the case the majority of times, and that is why I work with generalisations and not absolutes).
Basically everyone is right in a way. I was expecting this to be more... Contenty? Still, it started as a game and played out as a game but then it didn't go nowhere. Probably this is the main reason I had that opinion. As the Oracle said: Everything that has a beginning, has an end. Now this game didn't have the literal end one would expect. If I sounded "salty" it's because it was so great until I met the non-existent "end".