I would love to see an explanation of why you think putting the burden of proof on the new creator to prove that their new work does not violate copyright is ad

I would love to see an explanation of why you think putting the burden of proof on the new creator to prove that their new work does not violate copyright is advantageous to an auto-expiry approach. I can think of thousands of situations where what you propose would stifle innovation. Why is this way better?