I remember 1976 copyright changes. I'm that old, and I considered myself an author and publisher. I had registered copyrights in poems, and also had published an "underground" literary magazine. Any serious writer (I was serious, though not very professional) had to know about the rules.
I was also a programmer by profession, and a fan of the idea of copyright on my creations (as opposed to Trade Secret law). The "formalities" for code were yet to be solidified, but Adobe registered copyright in fonts around then like mad.
I bring this up because I think the "formalities" of the US law were always a bad idea. It barred many creators from getting paid for their work. (The "work for hire" transfer of property rights automatically that was also passed in those years was corporate rape of creators at its worst, but it somewhat improved the lot of the capitalists)
The "private registry" concept is close to the music copyright system of the ASCAP and BMI monopoly. I hate it. It's central authority without accountability.
Why do we want a legal system that is enforced by an Oligarch to "protect" creators? It can become a racket.