Most scholars in most fields make no particular effort to lay down the law on what topics scholars may touch on. Historians of the French Revolution do not have fits over scholars who dare to write on Italian History of the 11th-c. Any text (poem, classified ad, letter to the editor, post on an e-list) can be seen in any number of contexts. In recent decades (though I know nothing about it) Books as Books have become an object of study. Just before I went blind, one of the last articles I read in CI was focusing on the importance of spaces; she referred to Pound & Joyce as pioneers in making typography significant. I believe it was a German scholar of the last few decades who has done important work on how the typewriter helped form human consciousness of the last century or so.
If one doesn't like biographical criticism (whatever that is) don't do it. Why have conniption fits over those who do?