Depends on the library. I worked at one over 10 years ago and there was a low intensity battle between the head librarian (a cool former hippy guy with a pleasant demeanor) and the city appointed nepotism hire head of library resources (a bitter racist lady who was an open young earth creationist).

Since the resources lady was married to some city official, she had more away on her side to completely remove stuff from our science section. She kept removing stuff about black history too. Right when I was leaving she was having a fight, that she framed in terms of grant money, to install an explicitly evangelical wing of the library complete with a Bible study corner and regular visits from her preacher.

We had a more normal Bible study group that would meet on Wednesdays and even they were against her. America sucks.