You're right, and I left that out. If we deregulate and get the "ebil gummint" out of this, authors and inventors would be on their own, as I said, but the corrollary would be that it might be harder to build on previous inventions.
The implicit deal that inventors have with the public is that they disclose the details of their invention in return for a period of guaranteed monopoly. Without that built-in monopoly, they would do everything they could to obscure how their invention works, to be able to stave off imitators as long as possible.
Which, if you look at many patent applications, is not so far from the case now, *with* patents.
Authors and other "expressive" creators would have no such option. There's nothing to keep secret in expressive works.