Whenever I use the word “composition,” I'm only talking about writing (and producing recordings of) songs. Sometimes the word “composition” makes people think of writing notes on sheet music, which isn't happening here.
Many of the most important parts of popular music can't be notated on staff paper. Sound, attitude, mood, image, and inflection are all incredibly important components of a recording, but those elements can't usually be communicated to the audience via a sheet music translation of the same song.