I think most people who have thought about it understand the impact AI models seem destined to have on writing (and digital 2d art, soon music, and later other things). In addition to writers and voice artists panicking, see the Hollywood strikes, for instance, and what's currently happening in the corporate world to digital artists.
Copyright is not the correct tool to address it. In the U.S., the basis for copyright law is a clause in the constitution which allows Congress to pass laws to secure for limited time creators' exclusive rights to their creations, for the purpose of "promot[ing] the progress of science and useful arts."
If AI is going to displace nearly all of that content, at least content that's mostly entertainment and less educational (novels, music, images, eventually movies), doesn't that imply that AI is better at generating useful entertainment than humans are? Aren't hypothetical laws restricting training of AI on past works to protect the market for future human-created works a direct violation of the constitution, if AI is better at generating "useful" entertainment (entertainment that people will buy) than humans are?
To whatever extent AI can eventually displace nonfiction content in the sciences and liberal arts, which is more indisputably useful, the same argument will apply; however, it applies to fiction content first, because current AI models have more trouble with facts (trouble in the form of hallucinations, for instance). The threat in non-fiction areas of creativity is more distant than the threat in fictional areas of creativity which are not as bound to reality.