I see this held up as an example a lot, but the fast inverse square root algorithm didn't originate from Quake and is in hundreds of repositories - many with permissive licenses like WTFPL and many including the same comments.
GitHub claims they didn't find any "recitations" that appeared fewer than 10 times in the training data. That doesn't mean it's a completely solved issue (some code may be repeated in many repositories but always GPL, and there are limitations to how they detect recitations), but from rare cases of generating already-common solutions people seem to be concluding that all it does it copy paste.
That may be true, although even GitHub doesn't know for sure. But the problem remains: they're reproducing other people's code without regard to license status.
GitHub claims they didn't find any "recitations" that appeared fewer than 10 times in the training data. That doesn't mean it's a completely solved issue (some code may be repeated in many repositories but always GPL, and there are limitations to how they detect recitations), but from rare cases of generating already-common solutions people seem to be concluding that all it does it copy paste.