Games aren't art.
There's only two definitions of art I can see somebody using:
1. It's just pleasing to the senses. That could be anything from a lap dance to a renaissance painting.
2. It's commonly agreed upon that it's pleasing to the senses. This is usually more morally acceptable and therefore "traditional" I guess.
AFAICS, having artistic merit doesn't really mean anything. Not unless you are perhaps trying to express a social message of some sort.
From what I can tell, this game is just about chilling and wandering the desert into your grave. What's wrong with calling it art?