I would argue (today) that all writing is copy writing. Including journalism, reviews and other forms, because it is essentially promoting the worthiness of its own subject e.g. promoting the experience of listening to music, in the case of an album review.
In that sense, it’s like philosophy. It argues for its own existence.
.. Except philosophical arguments can undermine their own existence. It’s the only academic subject that can, and does.
Okay, so I would say philosophical writing isn’t copy writing.
As for art – novels, plays, poetry. That’s the most self-promotional writing of all, isn’t it? Because all writers are egotistical and are arguing for a legacy. Art promotes a feeling in you, copy writing promotes a feeling for you to put money to. Copy writing, therefore, is an extension of art. So all writing would therefore be copy writing.