If these are so easy to identify, why not just incorporate some kind of screening into the early stages of peer review?

What makes you believe that are easy to identify?

	▲	emil-lp 5 hours ago \| parent \| next [-]
		One could require DOIs for each reference. That's both realistic to achieve and easy to verify. Although then why not just cite existing papers for bogus reasons?
	▲	jordanpg 3 hours ago \| parent \| prev [-]
		Isn't that what GPTZero does?

Because real work takes time and effort, and there is no real incentive for it here.