If a company doesn't want to manufacture something anymore for whatever reason, that is their call. That's freedom in a shell really. However, I am still in awe that cancel culture continues to carry on in the United States. Over here in the conservative county that I live in we just wait for what the next absurd thing that is going to get cancelled could possibly be. I hear that Disney is on the chopping block next.
Then they should stay out of it if anyone else decides to publish those books. They lost their (fake, IP-based) "ownership". They were entrusted with his legacy, they vandalized it instead.