Surely what matters more than detecting generated content is verifying that the information is true and consistent and limiting the quantity and length of submissions per verified user of a system.

That takes care of the quality of the submission. The other part is determining attribution. Why not just ask the human submitter to defend their work in a controlled environment? If they can, it's their paper now.

I don't see a difference between unassisted people turning in crap vs assisted people still turning in crap.