This is very anachronistic and factually untrue. Design has only been a commercialized and institutionalized occupation for the later part of the modern era. Before then the roles were reversed. Art before then was always the heavily institutionalized and rigid practice. An artist studio during the renaissance was more akin to a factory with highly educated staff churning out stylized and "functional" artwork for church and state. This all changed in the 18th and 19th centuries when the artist became more associated with bohemian life and the mode of production and the art market changed (became more privatized and merchantilism expanded). Design and architecture on the other hand changed from something that lowly "craftsmen" and random educated people engaged in on a hobby basis into a regulated industry. This processes got crystallized with the ideals of modernism and functionalism in the early 20th century. Ideas which prevail to this day.