Case law is still pretty young in this area, but it’s looking like there’s nothing actually against copyright about the training of AI on copyrighted content. It’s not something that a license can restrict because the trainers can simply reject the license and carry on training under the basics of what the law allows them to do anyway.

Open source licenses only have power because they grant permissions that people normally wouldn’t have and put conditions on those permissions. If you don’t need those permissions then you don’t have to be bound by those conditions.