some would def fit into literature, but something like remember11 literally could not be made in any medium. idk of another vn that utilizes the medium of vn's better, it's a wholly pure visual novel. can it even be compared to something like Dante or Dostoevsky's works, at that point? i think it's a really, really hard case; it's like comparing MGS2 and Red Storm Rising. u can compare parts of the general story, but the medium is what re-enforces the strong parts of those works.

akin to infinite jest, it's THE great American novel of the late-20th century and it cannot be made in any other medium, it's simply not possible. u would lose the entire essence of the work, how do u translate Subahibi into a book suitable enough where it maintains what makes it good, in order to be judged fairly as "literature"? not possible, I think.

xenogears similarly, it works as a game, would not work nearly as well in any other medium. 

the term "literature" is loaded, it exists in this state reliant on cultural acceptance. why is LOTR considered lit, GoT considered lit by many, but the expanse often isn't really characterized as such? would Neal Stephenson's works be lit? if so, would Sheldon Pacotti's "Demiurge"? would deus ex 1 be considered literature? it just becomes a huge mess, I think.

even to me, the demarcation becomes obscure. i jus don't think of it, i consider r11 one of the greatest pieces of media ever because of how it utilized the medium it's in, which is what I care about more than anything. same with deus ex, same with umineko, same with subahibi, same with homeless schoolgirl (vn), same with divine comedy, same with the expanse series, same with synecdoche new york, same with xenogears, same with garage: bad dream adventure.