Absolutely, there are original ideas. And Waldo said it best.
Human beings can't create (make something from nothing). We can only invent (use pre-existing materials and concepts to form new objects), but there's always more to be discovered in this way.
Music is the best example. With only 12 notes (in the West), musicians continue to explore new ground. Not just new twists on old styles, but new styles and flavors, new instruments, new progressions and flairs, etc. It's simply amazing. Just thirty short years ago, nobody had heard anything like Korn, Tori Amos, or Guns 'n' Roses. When my parents were young, nobody had imagined an electric violin or computer-modulated singing.
Like with anything, most works fall somewhere into the realm of the ordinary, the flawed and trite. But some will always break free of that.
A non-gaming writer I like, Father John Richard Neuhaus, often talks about "the cult of the new". Especially in our time with such rapid developments in all aspects of society, many people make the mistake of equating newness with quality. New does not equal good. Many of our best inventions are refinements of old works, because no work is ever perfect. Still, new can be good; and new is always possible.
Don't give in to cynicism. I'm no technosoph or utopian dreamer. Our capacity for progress in this world is limited, but there's always so much more to do. So much more.