It would still be protected in copyright terms. Copyright exists as soon as it is created. Add to that your post here is time stamped but realistically only accessed by a relatively small number of people. In my case, my audio is also converted into video (time stamped) and uploaded to YouTube (time stamped). My lyrics are stored in the cloud in documents with version history turned on. When it comes to proving I had the earliest access with a provable development…. I am pretty covered.
A more advanced level of recorded completeness protects your copyright? Where did you hear that? Every version has copyright. Protection comes from proof of earliest possession and a provable evolution/version history. The more ways you have of demonstrating prior access to something, the stronger your copyright protection. Copyright of a specific version of a song depends on the recording of that version. So say I write a song that is a single verse plus chorus. Copyright exists as soon as it is committed to a recording. Ok, copyright exists on written lyrics and written out music too, which can exist before the recording, though copyright on the combination of lyrics + music exists at the moment they are committed to a medium together. For someone to build upon that song legally (writing wise), it needs the permission of the original writer to do so. The original writer can create new derivative works any time. In the USA they can do a cover once a public version has been released, though they would need to acknowledge the copyright and pay the songwriter the appropriate license fee, the same as any song.
Better recordings don’t protect better. Proof protects better.
Proof doesn’t stop people stealing your work
In the grand scheme of things a release downloaded by 500 people is no better protected than a song posted here.
If someone rips off one of my drafts, it is still built on my draft. If they can rip it off in a way that the similarity couldn’t be demonstrated, then they could just as easily rip off the finished version.
True, in the USA currently, registration affords you better compensation in terms of damages. If the artist made enough to make damages worthwhile I would probably have benefited more from publicity (and they lost more due to the same issue).
PS. This topic is in a critique area!
Over the years there have been a very, very small number of songs ripped off that were posted on this forum. In every case I have been aware of I have helped the writer/artist in question by contacting music sites publishing the copyright violating work and the offending work has been taken down. Often the site owners (Soundcloud, Google, Apple, Spotify etc) will suspend or ban the offending artist. Google will also stop that artist’s version and pages that contain it from being indexed by search engines. The result being their rip-off version goes nowhere and often the offending artist’s career is often damaged, if not over.
Two types of such copyright theft I have seen online have involved ill-informed and immature writers passing the work of others as their own, based upon a flawed understanding of the term “fair use” and “freely available”, and disgruntled collaborating partners. Even registered copyright would not prevent such idiots from trying to steal your song. People who know better aren’t usually that stupid.