People who commission art don’t call themselves the artist. That’s the big difference. If people found out you commissioned the painting that you later told everyone at the party that you painted yourself, and that it is practically your work of art, because you gave the precise description of what you wanted to the painter, and thus you’re an artist. Then you would be the laughing stock and the butt of many jokes and japes for decades. Because that’s ridiculous.

You just described SVN. It’s what we used before the invention of git. And is still used today for team projects that use complex file formats, like images, binary blobs, 3d models, that sort of stuff. It will work with any files.