One thing I have been thinking about, and that might contribute to these kind of comments, is that games lack an "artsy" middle ground.
Is this because games are such an extreme format? Games are very far removed from the kind of attitude that allows people to enjoy just about any other medium. Even reading a romance novel or watching a soap opera is more similar to playing an artistic game than playing a regular game.
As a work of art, Bientôt l'été is hardly excessive. I can think of many far more challenging works in other media. Games are just so extremely different from any of those media that allow for a wider variety of experiences.
I tend to dismiss games completely as a medium. But that's not how gamers see it. Makes one wonder how they can even deal with reading a book or looking at a painting.