As a bit of an Anarcho-Libertarian who is often in the middle of these conversations from either side, I would imagine part of the problem is your framing of this issue as if it is only coming from one direction, when there is plenty of evidence that both sides are into things like banning books[0] it's just a question of which books they want banned.
The both sides framing is a common tactic used to make this seem even but there’s a pretty notable difference if you look at the details. For example, Newsweek’s right-wing owners love this framing but the left example is a single school district removing a book from the curriculum whereas the right wing examples are far more widespread and include books being removed from libraries. The motives are also different: banning books which depict racism positively (highly debatable in this example) is different from banning them because they reflect existence of gay people in a positive manner.
According to the article that I linked, California has banned "To Kill a Mockingbird" in schools due to racism and you seem to be implying that is because the book "depict[s] racism positively"; however, I read it back in school and I remember discussing extensively how the book showed racism in a most negative light.
It doesn't seem to me like you are willing to believe that both sides could be over stepping here, but I personally am sure of it.
I remember the discourse around changing Jim's name in Huck Finn and banning To Kill a Mockingbird. Those changes and bans were wrong. But still the scope and intensity with which the extreme right are gunning for books is alarming. They're doing it more, it's more widespread, and they're using state power.
When "the left" has opposed books they try to use social pressure to get book settlers to voluntarily not stock those books. The right is currently using state power to prevent the teaching of certain books, their presence in public libraries, and are even suing to make private sales of certain books a crime in Virginia.
> Apparently no one told him that the stack of books in the photo included one banned in the state he leads, To Kill a Mockingbird, which was banned from California schools on the grounds that it contained racism.
Clear cut, right? Nope, here’s what their own linked article says:
> Schools in Burbank will no longer be able to teach a handful of classic novels, including Harper Lee's To Kill a Mockingbird, following concerns raised by parents over racism.
> Until further notice, teachers in the area will not be able to include on their curriculum Harper Lee's To Kill a Mockingbird, Mark Twain's The Adventures of Huckleberry Finn, John Steinbeck's Of Mice and Men, Theodore Taylor's The Cay and Mildred D. Taylor's Roll of Thunder, Hear My Cry.
This is how the false-equivalence machine works. A single school district is expanded to an entire state (15k students isn’t nothing but it doesn’t represent many of the ~6M students in the state) and is presented as the equivalent of multiple state-wide attempts to remove books from schools & libraries, and again ignoring the difference between removing something from the curriculum with the goal of exclusion versus inclusion.
The urge to censor isn’t unique to right-wing politics but since they’re the ones pushing the most aggressively and successfully, I attributed more of it to the people causing the lion’s share of the harm.
[0] When It Comes to Banning Books, Both Right and Left Are Guilty | Opinion: https://www.newsweek.com/when-it-comes-banning-books-both-ri...