Do you believe that banning books from public schools and public libraries is a form of Political Correctness?
How do you think it relates to Freedom of Speech? Is being "obscene or harmful to minors", by whoever's measure, a sufficient reason to suppress the distribution of books at libraries? After all, adults can still buy them online, so it's not really censorship... or is it?
I'm not the best friend "freedom of speech" ever had. Trump and QAnon are Exhibits 1 and 2.
Speech isn't 'free' in any absolute sense even in the US ─ there are still laws against defamation, incitement to crime, conspiracy, incitement to sedition or public disorder ─ and so on. They're common to all Western countries that I'm aware of and as a rule I have no argument with them.
But the editing of libraries is usually more a matter of trying to impose religious views eg deny the literary existence of homosexuality and so on. A well-run children's library has books according to age / maturity, doesn't push religious or political views, cuts a lot of slack, draws a few lines.