The headline and intro to the article cite the DMCA but the bulk of the examples reference UK and EU law. Additionally, most of the examples aren't related to copyright at all. Generally seems like a misleading article intended to conflate spurious takedown requests with DMCA requests (which can also be spurious, no doubt).

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).

You could require having your claims verified by a trustworthy party (or at least a court) before being able to send them.

The lack of verification, even just of the sender's identity, is just insane.

Or require the claimant to specify a dollar amount of damages, and be required to pay double that if the claim is ruled frivolous.