It's true that we usually think of the sun's appearing to "rise" as being due to earth's rotation -- not due to the motion of the sun itself. But it's also true that, from the frame of reference of the earth, the sun does rise in the eastern hemisphere of the sky. "From the frame of reference of the earth" is the key phrase there, and we can choose any reference we want to describe motions. So, in this sense, there really isn't anything wrong with claiming that "the sun rises in the east".