I'd contend this is not true. Even professional authors go to an editor who identifies things that need to be fixed. As the author of the text and knowing what it should be, it can be difficult to read what you wrote to find those mistakes.
> In exchange for that your audience gets 3-4x length normalized bullshit to read instead.
This is not at all what is implied by having an AI act as an editor. Identifying misplaced commas, incorrect subject verb agreement (e.g. counts), and incomplete ideas left in as sentence fragments.
You appear to be implying that the author is giving agency to create the content to the AI rather than using it as a tool to act as a super-charged grammerly.