Ironically, this could turn out well for the GPL
If copilot can't inform its users which license(s) applied to the code that it "regurgitates", then the only legally safe way for it to be used (I expect) is for Github to require all copilot users to license their resulting code under the GPLv3+. After all, it's the only(?) license that has the property of vaccinating derivative works against becoming non-free software.
While it's possible that some instances of regurgitated code might not contain GPL'd code, what corporate lawyer would be willing to advise their clients to accept that risk? Ironically, copilot could increase the use of the GPL. :-) That's assuming people would even continue to use copilot. It's probably more likely that corporate lawyers would warn their clients' developers not to use it.
Another alternative of course, is for Github to throw away all of the "learning" that copilot has done and start again from scratch but this time scrupulously excluding all GPL code (and any other vaccine licenses that might exist).
Biting the hand that feeds IT
