Do you think this Copilot is some sort of advanced AGI who just became a genius programmer? Almost every piece of code that it "generates" you will find it almost verbatim in one or several public repos.
If you ever tried AI Dungeon before it imploded, you'd agree GPT-3 is pretty impressive and is generally capable of coming up with original stuff. Obviously with a bias towards the kind of stuff that's in the training dataset, which is why you try to use a very broad dataset. But still original.