When librarians speak of banned books, they are talking about books other people wanted banned, not the books librarians themselves wanted banned.

Harry Potter gets on these lists because some christian groups in America demanded that librarians remove the book from their shelves, while the librarians didn't want to. But books that the librarians themselves chose to not stock don't get on the list, because to a librarian, a librarians job is to select which books to stock and which not to. You are very unlikely* to find a copy of Myth of the 20th Century on the shelves of your local public library, not because of external pressure but because the librarians themselves think that people shouldn't read it. And to librarians, that is not banning.

*(I checked. Of the two library systems I have a card for, one doesn't have it and the other has a single copy in German, which they won't let you check out, but no copies in English. Since this is an American library, the German copy would be inaccessible to huge swaths of the population anyway.)