He and Dali have become poster art and commercialized, which is a testament to the fact that they made some cool looking stuff.
Because of that, most art history will scoff at them.
I still think he did some cool stuff - more of an illustrator I guess - the cool thing is that his stuff was done in lithograph which is a step or two harder than just regular charcol pencil and he had no real formal math background, just figured it out based on what looked right to him.