That title didn’t really work out. Anyway, some quick words about the notion of a ‘videogame canon.’ As usual, I’m completely behind the times (or… Fashionably Ungleichzeitig) and am going to give my opinion anyway.
Canon is an execrable thing, a form of selective memory. Let me give an example from the most appropriate source: the ancient Classics.
Ancient texts from the Mediterranean world were written on perishable materials. In order to be preserved, they needed to be copied. Copying, for most of the history of literature, had to be done by hand, which meant employing what was, at the time, highly skilled labour for extended periods. Literature was expensive, and the reading and copying of books was the privilege of an elite.
Consequently, the received Classical canon is the combined result of thousands of years of happenstance and the tastes of various economic and cultural elites. This leads to all sorts of strange situations. For example, one playwright (Aristophanes) stands in for an entire genre (Attic Old Comedy).
The capriciousness of the canon is especially cruel in historiography (the writing of history). Before it was annihilated by the Romans, ancient Carthage was a literate civilisation that produced its own historiography. The work of least one Carthaginian historian was translated into Greek, which means that it was a part of the pool of literature from which the Romans, and later Mediaeval and modern Europeans, drew when forming the Classical canon. It just didn’t get copied. Not only did the Romans destroy Carthage physically, but they have passed down only their version of events. What the Carthaginians thought about themselves, the Romans, or anything else is lost forever.
Videogames share certain properties with old manuscripts. Preserving access to them is difficult. Hardware and software incompatibilities, DRM, technical complexity and sheer disinterest are all potential obstacles to their preservation. When they are preserved, the opinions of the preservers, of the intended audience, or of those authorising the preservation will colour what is chosen and how it is presented.
I’ll finish with the example of Marathon, released in 1994 for the Apple Macintosh. Marathon is a first-person shooter that is credited with being the first in the genre to introduce a vertical viewing axis, mouselook, and dedicated multiplayer maps. It also told an engaging story which raised the same issues of player/avatar agency for which Bioshock was later praised (and did it better, frankly). Marathon was an excellent game that attracted some fanatical fans.
Marathon did not make it into the Smithsonian’s videogame exhibit. Its narrative is neither heaped with critical praise, nor regarded as a significant moment in the medium in the way Bioshock’s is. Marathon rarely makes it into a ‘top 10’ list of anything. The probable reason for this is very simple: Marathon was released for the Apple Macintosh and not for a PC or console. With only a relatively tiny audience and no direct competition, Marathon never really permeated the consciousness of the audiences and developers who get to decide what counts as significant.