You can configure Copilot to not return code that appears verbatim in public repositories. In that case it at least won't produce code you could legitimately argue would be covered by any individuals' specific license.
Copyright is not meant for utilitarian purposes. For that there are patents. The non-utilitarian, artistically expressive aspect of software is in how code is organized. You know, the rather arbitrary decisions that spawn hours of bike-shedding.
Copilot is most useful when it makes no creative decisions and instead follows the style and design patterns already established in the code base.