'The medium is the message' is a famous quote by Canadian media thinker Marshall Mcluhan. Interesting guy. Look up the quote to get a better sense of what he meant by that. Film is an old medium for art, so your points make sense in that context, but there are new technologies for art in which your points are no longer valid. As I mentioned, it's difficult to penetrarte the mind of any artist, but working with them challenged my own assumptions about the meaning of art in general.