Not really, no. It’s just the “poor man’s copyright” (aka mailing it to yourself) that is completely meaningless, useless, unenforceable, and legal fiction.
You create something. As soon as you put it into a “fixed form”, you have the copyright to it.
At this point, you have two choices. You can choose to publish it, or not. If you do publish it, then you’ve pretty well established its date of creation (or at least the date it was published). If someone comes along later and tries to sell copies of it, you can stop them. Since you didn’t register it, you can only sue for actual damages. If they make a hundred copies and distribute them for free to their local book club, they haven’t done you any harm, so your actual damages are zero. You can’t sue them for statutory damages. That’s the benefit you get from registering the copyright, which you didn’t do.
But what if you don’t publish it? Technically it’s still covered by copyright, but now the burden of proof is on you. Mailing it to yourself does nothing. But there are plenty of other ways to prove that you created it.
There is a valid point here that proving it is significantly more difficult. The idea that just creating something gives you the same protection as actually registering the copyright is obviously false. But the law isn’t worthless, and it gives you a lot of protections that you wouldn’t have if registration were required.
The “poor man’s copyright” is completely worthless.
If you really care that much about something, pay the $35.
Well, all forms of ownership are a phony legal fiction, if you want to go down that road.
But copyright seems to me less obviously so than most other forms of ownership. If I literally create something, haven’t I a much better right to claim natural ownership of my creation than anyone else? It’s more obviously true that I own the novel I wrote, the painting I painted, etc than that I own this stretch of land, which existed long before I came along - indeed, long before any people came along. Ownership of land is much more of a legal fiction than ownership of created things.
While being able to establish you wrote something on a certain date might be hard back in the pre-internet days, it’s pretty easy to find somewhere where you can post something with a date that you would not be able to tamper with. For example, a twitter post on an account that’s set to private. Or a private YouTube video.