They could try to trace every single code snippet they train on to its "true source" and use the license for that, but that's not very well-defined, and is a lot harder, and it's never going to be 100%.
To use the old trope — if the majority of programmers can't implement Fizzbuzz, but they do have a Github profile, are they being included too?
Hopefully there's some quality bar for the training set, i.e. some subset of "good" code (e.g. release candidate tags from fairly established OSS tools/frameworks in different languages) rather than any old code on the internet.
> Once, GitHub Copilot suggested starting an empty file with something it had even seen more than a whopping 700,000 different times during training -- that was the GNU General Public License.
https://docs.github.com/en/github/copilot/research-recitatio...