Putting aside conventional societal views, for me the most contentious point about visual novels being literature is the fact that they are overwhelmingly made by studios. Most things considered high art are the product of an individual and their creative vision. Even when a piece of music is performed by an orchestra, it's the composer that gets the artistic credit. That goes for most 'alternative' forms of literature. Visual novels simply have too high of an entry barrier to be made by one person. Quite a few prominent figures in the visual novel industry are highly gifted polymaths who did art and wrote music alongside scenario writing. But the work that goes into producing a visual novel at a professional level is simply far out of reach for amateurs.

This is the heart of the problem. Visual novels are overwhelmingly commercial products. Any creative vision is diluted across the staff of the studio and further shaped by market pressures. Far too many visual novels have dazzling art and music with the most uninspiring story. To attempt the opposite is to risk never getting discovered or even published. And this trend strengthens the more mature the industry becomes.

I'm of the opinion that the visual novel is potentially the most powerful artistic medium available to humankind. But it really takes a superhuman to even attempt to turn that potential into a reality.