Realistically, there are no banned books today, outside of stuff like Turner Diaries and Mein Kampf and terrorist guides. And even those (outside of terrorist guides) are usually just semi-banned, i.e. Amazon and most reasonable booksellers and libraries won’t stock them, but you can buy them by other means and it’s probably not illegal.
So I have no idea what’s your point here. The “liberals” who promote reading “banned books” refer to stuff like small school libraries not stocking whatever the American media and Twitter decided to wreak hysteria about this season.