Additionally, the premise that actual copyright takedown notices shouldn't be available to the public is nuts. Whether you agree with the DMCA's implementation or not, any takedown mechanism must be available to all copyright holders and not just corporations with legal teams. The DMCA process is already more onerous for individuals given that they have to provide a legal street address in an era of doxxing (or pay for a P.O. Box).
The lack of verification, even just of the sender's identity, is just insane.