Copilot doesn't recognize what you're trying to do and then paste a code sample from a repo it has in its index. Just like DALL·E 2 doesn't produce images that say "I picked these pixels from this image and this part from this other one and these colors from this third one". When a model is trained, it's effectively a set of hundreds of millions of numbers that when combined in just the right way can produce a specific output. In my experience the vast majority of the time Copilot doesn't write code that already exists. It actually uses the variables you declared, the functions that already exist in your code base, etc.
It's not an index of best matches from GitHub for what you're trying to do.
Also, if we agree that GitHub copilot enables you to be more productive as a developer. Can we argue that it could help open-source communities by helping them finish projects faster?
There could be a problem for open source projects (and closed source ones as well) if Copilot could autocomplete with code from private repositories. I can't remember if it looks at them too.
It's not like they don't get it. Even Microsoft will provide the source of its products under certain circumstances for this exact reason.
This is far from the truth. The main usage of most open-source projects isn't as code, but as a product. The median user of an open-source project wants to think about the project as little as possible. They want to be as unaware as possible of the code that makes up the project. They're happy to add the project to their `requirements.txt`, add a few lines to import and use it and then never think about it again.