If I use Copilot and it suggests a large block of GPL2'ed code for my project, which I then include, then that is a GPL2 license violation.
Whether the GPL2 will hold up in court, or whether the courts will uphold this specific case (e.g. can you prove intent? Do you need to?), is a separate issue entirely.
The next question is, can I use GPL'ed code in my product and then claim that it was injected by Copilot to avoid repercussions of my actions if caught?