Name one computer game created without any cultural or historical referents then, "from nothing" as it were.
If you mention Pong or Spacewar, you've already lost. Table tennis and the Lensman books, respectively.
Literally anything humans do is based on prior influences, referents and data. There's no aether out of which the "spark" of inspiration strikes, nor does anything emerge from the pure vaccuum, creativity is just neurons doing what they will with the information they already have. Therefore the only difference between human genius and the mediocre output of AIs is complexity, and the only question worth asking is how far that gap can reasonably be bridged.
It's understandable that this is upsetting, because it threatens one of the last bastions of human divinity, and no one really wants to believe human beings in all their splendor, subtlety and complexity are just a pile of ad-hoc stochastic wetware algorithms running on a hemisphere of gelatinous goo, no more divine than a stone on the ground, but eventually as this technology matures we're going to have to come to terms with the fact that creativity can be manufactured, just like anything else, and like anything manufactured, its quality will inevitably surpass anything humans are capable of.