The default designation of poetry has become written poetry. That's why we have to prefix the adjective "oral," because the unmodified noun no longer covers anything but written poetry. That's also why we resort to other unwieldy phrases to pigeonhole events and phenomena that our cultural proclivities have silently eliminated from consideration. Thus a "poetry reading" describes a performance (from a published text, of course) before a well-behaved, often academic audience. Thus "spoken-word poetry"—so redundant from a historical perspective—identifies voiced verbal art, verse that is lifted off the page and into the world of presence and experience.
How to Read an Oral Poem (2002), p. 30