Oh man, I sure have a lot of hot takes regarding this subject, the first one being that Academia sucks ass real hard.
I spent nearly 10 years studying philosophy on university and academic circles and I abandoned all of that and never looked back. I really liked the idea of bringing game design and psychology into the table to discuss onthology, methaphysics, aesthetics and other broad “philosophical” subjects and I always had to deal with weird looks and remarks and every essay or lecture I did on this subject had to be preceded on a justification on why this was interesting or valuable in order to start talking about what I thought was truly interesting.
The reason you won’t see certain types of games discussed in these environments is, deep down, the same I had always to battle prejudice when I was interested in doing that anyway. I will basically paraphrase Pierre Bordieu here but if you are interested in checking the source go for “Distinction: A Social Critique of the Judgement of Taste”. The main idea being that the cultural world has reproduced a lot of dynamics of capitalism, turning the culture as a battlefield for the accumulation of legitimacy and “cultural capital”, in other words, prestige as a tool/weapon to legitimize certain ideas and establish hierarchies that are also a reflection of basic social and sociological dynamics (struggles for power, resources and notoriety in the form of public atention, to name one example).
Gamey games don’t carry the same “cultural” value as other games like That dragon, cancer or games that have accumulated relevance due to press coverage or receiving awards. You can’t pose or perform publicly as an art critic and defend games as a medium with stuff like Katamari Damacy or Terranigma because those games are not regarded as “art” or “deep” or “intelligent” the same way as Braid or Stanley Parable are (independently of how you personally feel about that). It is in a lot of senses a matter of popularity too, because Killer7, Flower Sun and Rain or The Silver Case sure aren’t “commercial” games or at least not in the usual sense. But since those games carry the stigma of mass culture, they have a harder time being presented as games with artistic or symbolic value. Bioshock on the other hand clearly is a “game” game but since it got discussed and earned that fame of having an Interesting Twist, it has an easier time featuring in these places.
I got disinterested in all of that because I realized that in a lot of sense it was just a performance. It is not about studying games or producing meaningful insights, it has a lot of do with presenting games in a certain way, fighting for that legitimacy and enacting artness and establishing certain dynamics so games are perceived as something with academic value.
Oh, and as @Video_Game_King said difficulty, time and accessibility have a lot to do with it too. Since you are not really interested in games, but in using them as a platform to defend or present yourself in a certain fashion spending the hundred hours in an RPG is absolutely out of the question. And also not logistically viable in the context of a college course or whatever.
Sorry for the rant, clearly I have Problematic Feelings™ regarding this subject, but I hope it helped anyway.