Given that many other projects (such as fedora) are adopting genAI policies, I think it may be helpful to at least give contributors a clear opportunity to disclose their use of Generative AI in the form of an easy checkbox alongside the existing DCO checkbox.
I think this should look something like:
This would be followed by a comment offering an optional place to explain in what way it was used (i.e. planning vs writing code vs translating etc.