This is my favourite poem and was before I even knew how layered and knotty it is. In addition to its obvious interpretation it's also about readers and reading, how even if you are the mightiest ruler who has ever lived you still can't make people read you a certain way - the sculptor who "mocked" his features may have found the king's intentions absurd even as he was forced to sculpt his likeness.
It was an illustration by Shelley of the problems of a certain school of literary thought at the time which held that the author of a text is the ultimate arbiter of its meaning. That Shelley was able to make such an elegant counter-argument and encode it as one of the most lyrically and thematically beautiful poems of all time puts me in awe every time I think of it.
The Death of the Author came about in 1967, even New Criticism, which foreshadowed Death, came about only at the earliest the 1930s-40s, after IA Richards published his Practical Criticism.
Shelley wrote in the Romantic period, when the artist's personal "genius" was paramount as a conduit to the "sublime". Saying that he somehow whipped up a criticism of "author as the arbiter of meaning" in what is practically a product of a friendly poetry contest is plainly absurd.
Strangely you also attributed this anachronistic reading to Shelley, making it somehow the author's intent to be counter-author-intent. Just... why?
It was an illustration by Shelley of the problems of a certain school of literary thought at the time which held that the author of a text is the ultimate arbiter of its meaning. That Shelley was able to make such an elegant counter-argument and encode it as one of the most lyrically and thematically beautiful poems of all time puts me in awe every time I think of it.