That's just not true. "Banned book" has meant "book banned from schools and libraries" for a very long time. This is the meaning used by the American Library Association.
https://www.ala.org/advocacy/bbooks/frequentlychallengedbook...
It is, for the time being and for most practical purposes, impossible to ban a book from being published in the USA. Other countries have bigger problems but that is not what people discuss in American politics.
>And did you find it just as egregious when Huckleberry Finn was banned in new york and california schools and public libraries for using the "n" word?
This is a very feeble gotcha.