I feel like this article is responding to a strawman. As far as I can tell, nobody in Possible Minds is arguing that corporations should never be restricted or that nobody should think about regulation. They're just saying that controlling AI is a critical problem in and of itself, which won't be solved by just controlling the corporations who build AI systems.

"Long before existentially troubling control problems will arise [...] these mediators will shape an immense number of decisions" - certainly a true statement! But true in the same way that Enron can create an immense fraud long before the energy market causes existentially troubling climate change problems. It would be hopelessly silly to read a book on climate change and respond that it should have been about accounting regulations.

(Sidebar: I don't think the title was cut off in quite the right place. "Moderation as a virtue" is a reference to one particular criticism by Ted Chiang and isn't really a good summary of what this article is responding to.)