The situation is complicated by the fact that the Librarian=MLS formula is not universal around the world. There are a lot of “librarians” (or cognate words) who do not have the MLS. Librarians in the UK can do it during the course of a normal undergraduate degree, as I understand it.
It is probably good to require all US librarians to have one, but denying the term absolutely to those without the degree is like claiming that people in Egypt can’t be called “drivers” until they get a US license.
