Nobody seems to consider the fact that non-US law is also applicable to this issue. GitHUB ToS are subject to US/California law, but that does not mean that GitHub must not respect copyright in other jurisdictions where the service is provided. Many common open source licenses do not have a governing law clause (i.e. BSD and MIT). Since one of the primary defences for Copilot is fair use, and this concept does not exist in EU it would seem that Copilot is even more legally iffy in other jurisdictions.