What I consider to be the barometer for what is a rock artist and what is not, is somebody who has a certain element of blues, even a hint of soul or blues music, derivative of African-American blues, folk, spiritual, or gospel.
Ian AstburyJay Z in many ways is a rock artist. In the sense that they've used hard rock, punk rock, psychedelic rock aesthetics and influences in their music. When you see Kanye West, he has a full band playing. Jay Z has a full band playing with Marshalls.
Ian Astbury