Thank you continuing this dialogue; I saw your bio, and though we disagree on this particular issue, I think we have a lot in common, and I appreciate your participation here.
Neither GOSH nor the government control who can create derivative works.
Unfortunately, that is not the case. They used their position to selectively control publication of works they didn’t approve. That’s clearly censorship.
But even if they only collected royalties, it would still be a free speech issue. Selectively assigning monetary costs to certain speech is an abridgement of free speech, for the same reason SLAPP lawsuits are a free speech issue.