What is the design style called where they create form with simple shapes, usually triangles like they have done with the ground in the Chrome Maze Experiment
Or like the images below:
I call them origami illustrations.
While we could trace the aesthetic back to various art and design styles such as the aforementioned cubism, there are some more recent terms such as low-poly or faceted illustration. Tim Reynolds was one of the earlier users of the style.
It can be done via 3D rendering (where it originates...essentially reducing the polygons used to render a complex object), or 2D filters (or just by hand). There's an App for it too: Dmesh
Related to it would be voxel style which, instead of connected planes to create a 3D shape, is used individual 3d shapes (such as in Minecraft).
Cubism is an early-20th-century avant-garde art movement pioneered by Georges Braque and Pablo Picasso, joined by Jean Metzinger, Albert Gleizes, Robert Delaunay, Henri Le Fauconnier, Fernand Léger and Juan Gris1 that revolutionized European painting and sculpture, and inspired related movements in music, literature and architecture. Cubism has been considered the most influential art movement of the 20th century.2 The term is broadly used in association with a wide variety of art produced in Paris (Montmartre, Montparnasse and Puteaux) during the 1910s and extending through the 1920s. Variants such as Futurism and Constructivism developed in other countries.
Pablo Picasso paintings.....
The style is "cubist" or "cubism"
but I think the images you post have a definite digital feel.
I would call them "cubist illustration" or "digital cubism" if I were trying to specify and illustration style.