Earlier quoted context omitted.
If you are putting up code on GitHub to which you don’t have all the rights you’re actually in violation of their TOS and you are violating the rights of other copyright holders. I understand this is common and may not violate community norms or expectations but it is technically a license violation on multiple fronts. Contributors who add to existing GitHub projects are providing the same license to GitHub as the pr…
I guess the Github Copilot authors did not handpick projects they checked were legitimately put on Github. So they are accomplices in that case.
Beyond that, that's what DMCA takedown requests are for. Github would only be an accomplice in that case, if they got a legitimate DMCA takedown request and chose to completely ignore it.