I just had a thought.
Could the author/owner even retain copyright if they change the content? I mean, it where’s the point where it stops being the original and becomes a new work?
I guess this is beside the point though as copyright is automatically granted to pretty much anything at the time it is fixed it the medium. So even if a million variants of the text were made, the one making the variants owns a million copyrights. Which would be unmanageable to register. But still legally enforceable possibly.