Thankfully here in the U.K. we don’t need copyright registration, but I think the copyright system is, because of the international nature of copyright infringement, still prohibitively expensive for the users who would benefit the most from it (that is, small businesses like mine). There’s still value in copyright protection, though for software in particular I think it is rapidly being eroded by the rise of Internet piracy and the implicit pro-piracy stance adopted by privacy campaigners and ISPs.
If you prevent enforcement of copyright and systematically stick roadblocks in the way that make it too expensive to clamp down on infringement, there does come a point when the benefits outweigh the “fair use” rights and the fact that your work will eventually enter the public domain. That is, it becomes a one-sided deal and is no longer operating in the favour of the creator.
I am, to an extent, of the opinion that that point has already passed, which is why we’re seeing things like DRM which are only necessary because copyright is not working. DRM and copy-protected files don’t really need copyright in order to function; it could all be handled through the contract between producer and consumer, and in that case fair use rights and the public domain requirement no longer apply—they are solely a feature of copyright, not some more fundamental right as I think people sometimes assume.
The irony is that the people stealing copyrighted material think that copyright is a bad thing (or they tend to say that they do), when at present it actually gives them more rights than they would have without it.