For sure. I agree 100%. I have spoken a lot about this in my field in academia, research time has shrunk to minutes and not months. Before AI, you had to read through all of the material to get to what you were looking for. Now, you can ask for example gemini deep research to do preliminary research in less than 10 minutes. It will provide you in some cases a list of 100 sources that you can then use. Where it took 6 months to make that list, you can now do it in 10 minutes.
But when it comes to writing, even grounding it in all of these sources, it really cannot even compare to humans. My work is in academic philosophy, but as you noted in creative writing, where minute details can really determine a whole plot, AI would suck. I know when I read fiction, I pick up on details. And from my experience, when you use AI, it forgets those small details.
And yes, I am sure we are heading into an era where we will see this - Google etc. publishing something they trained their AI on our private data. But I think the real problem, the one we will see very soon, is where this happens - AI training on private and stolen data - when another person uses AI and "steals" your ideas. That is, I prompt AI, and then use that idea I thought was novel and my own, but in fact it comes from another person's private work.
Crazy times.
Sorry for only replying now!