Now that I think about it, you're probably right. It just looks so "goofy" to my eye, as in, "What interstellar galactic battle were you in that THIS was the result?" The other damaged areas are clearly/obviously/visually "direct hits" from enemy ships' laser cannons. Whereas this one always strikes my eye as a dropped prop that caught the corner of a table before hitting the floor, and film scheduling was too rushed to repair it since it would likely never get seen. But now that I'm saying it out loud, I wonder if there is a scene in A New Hope in which you can clearly see this area on screen?