I was thinking about this more. I think that he said that he doesn't have time to think about whether his work is literature or not. I think this is a very well-mannered way of taking an anti-establishment position towards institutions that make judgments and decisions about inclusion of a body of work by a particular artist in the canon.
I think that what the canon is called, is works that are studied in universities. I think it must be nice for an artist to know that they are included in the canon. If it means nothing else, it means that their work is many-faceted in a way that is of interest to scholarship.
But I can understand why an artist would reject the relevance of a scholarly establishment to their work. I think that looking at it in the most pessimistic way possible, scholars are vampires who are profiting by the creative work of others. They're people who are paid to decide whether or not something is literature, and yet they aren't creating it themselves.
So, I think Dylan has a point in saying that he doesn't have time to worry about whether he's creating literature or not. He's too busy with creating his work.