Only then will we see an answer to the question "is making an AI write your stolen code a viable excuse".
I very much approve of the idea of Copilot as long as the copied code is annotated with the right license. I understand this is a difficult challenge but just because this is difficult doesn't mean such a requirement should become optional; rather, it should encourage companies to fix their questionable IP problems before releasing these products into the wild, especially if they do so in exchange for payment.