You make it sound like Copilot is just copy-pasting something from a single repo. The code Copilot generates for me is extremely specific to my application. It understands the context, my code style and what I'm trying to do.

The result looks like my own code and is utilizing the already existing parts of my application. The code it writes for me solves problems that you cannot find a standard solution for anywhere and is definitely not something that could be attributed.

How Copilot is trained is an issue but answering the question "where did this code come from and what license is it under" would be impossible.