The current argument AI owners use is that it falls under fair use as "transformative use", so the licence is entirely irrelevant. If that wasn't the case anything trained on GPL code would have to be released under the GPL.

I'm now sure what if any argument they are using in Europe. Most countries here have a "fair dealing" exemption which is similar to USA "fair use", but it doesn't include "transformative use". The closest would be "pastiche", but that wouldn't really cover it.