You’re right, and other intellectual “design” jobs will have physical or visible manifestations of the design process. In video you have a storyboard, set design. In music you have notation, lyrics, demo recordings, and so on.
Right! For music, I think it’s even like saying… The process of making music is much more than just literally performing it… But it’d be weird for the creative process to not contain any playing-of-music that looked in some ways like performance.