Spanish (or the dozens of romance languages and dialects that would eventually converge to it, anyway) predated Arabic in the peninsula, and survived it. As a consequence, we study arabic presence as an invasion/influence that came and left, rather than "what our culture was" at the time - whether that's fair or not is an entirely different topic, but the point is that I can perfectly read the literature made in romance languages since it hasn't changed that much. Even latin would be somewhat understandable.