Censorship is when a community tries to give input into what books it wants in its library.
Appropriate decision-making is what it is called when a librarian decides for the community.
Librarians are mostly liberals and library’s book selectors are mostly liberals. Review tools that book selectors use in collection development are produced and written, mostly, by liberals.
People who use libraries are mostly liberals, cheapskates, kooks or a combination of all of the above.
This is based on first hand knowledge. :)