Philology is a branch of English academia, described on Wikipedia as "a combination of literary criticism, history, and linguistics". I am no expert, but its central premise appears to be that these three subjects are essentially indivisible for a proper understanding of a text.
Tolkien, in his letters, described himself as a philologist, as does Tom Shippey, one of the few academics to have made a serious study of Tolkien's work.
In the introduction to his book, JRR Tolkien: author of the century, Shippey states that the teaching and study of the subject is in decline and has practically vanished from universities. But he does not elaborate on the reasons why he believes this to be true or why it might have happened.
Is he correct? And if so, given the obvious utility of the subject (the value of the premise with which I opened this question seems pretty incontestable to me), why has it declined?