there’s a difference between an author providing information about the text and an author stating their intended interpretation of the text
Tolkien saying that he meant the Shire to be analogous to Oxford and Minas Tirith to Rome is a matter of intent
Tolkien saying that Dúnadan kings had the power to interpret laws but not make them is a matter of information
total rejection or unilateral acceptance of authorial input are not the only intellectually consistent positions thank you goodbye