I fail to see the relevance of this. As a publisher exerting editorial control, you also assume some liability for your content as that editorial control is a f

I fail to see the relevance of this. As a publisher exerting editorial control, you also assume some liability for your content as that editorial control is a form of speech. Printers who exert no editorial control are not engaging in speech and are thus not liable for the content they print (same with the ink, paper and printing press manufacturers.)