The more successful "self published" authors writing web novels make significant money from patreon (>$20k/month); this relies on copyright protection (but interestingly, just a few months would be sufficient for that business model).
The authors I'm aware of making >$20k don't do any significant gating. That practice is only really common with people republishing through Amazon (which probably demands it).
This is exactly what copyright is.
I agree that you could work around this in a world without copyright (e.g. by watermarking content and blacklisting), but it would be difficult and make the whole profession less viable.
Mass distribution and payment becoming accessible/low overhead was an extremely helpful development for authors in my view, and removing copyright would have the opposite effect (but cutting it down even to several years would change surprisingly little).