Librarians are expert in classification. Let’s rate them by their librarian skills.
“CLASSification”
Good one!
The Librarian of Congress job doesn't involve the everyday tasks of classification, just as the post of Surgeon General doesn't include surgery. They are both what you might call "cultural policy" jobs. Can do far-reaching, temporarily invisible, mischief or good.
She has a doctorate in Library Sciences and has worked or taught in the field all her life. I would say her skills are more than adequate.