I re-read to make sure I was not reacting off the cuff. Your list of good code practices is obvious what we want, but that is not going to happen with the way you describe working with AIs.
You don't seem to be aware of cognitive load; when you say:
"any time our instinct says "don't build that, it's not worth the time" fire off a prompt anyway, in an asynchronous agent session where the worst that can happen is you check ten minutes later and find that it wasn't worth the tokens."
That is going to fracture a person's understanding, leading to mentally fatigue them. People, and I see this coming from you too Simon, seem to be treating software development like it's a sprint, when it is absolutely a marathon. One that requires consideration before acting, and now with LLMs the common act of figuring it out along the way is now dangerous because they will happily guide one to create a CMS when all they want is a one off function.
I've written quite a bit about cognitive debt and load recently https://simonwillison.net/tags/cognitive-debt/. It's a very real issue - working with these tools is exhausting if you don't figure out how to pace it, and I've not figured out how to pace it yet.
I'm currently expecting this will be a temporary thing, brought on by the significant new abilities of the November model releases.
Simon, I'd be interested in a voice conversation with you on this topic. I've developed my own chain-of-thought system that is very different from what others are doing. Mine is a Socrate Agent that leads the developer, does not write their code, but guides them to become a better developer. It completely opposite the direction the larger industry seems to be going. Augmented synergy between the AI and developer, not the AI coding and the human overseeing.
Writing code is a social act even though few actually read it the code, they experience the result of that code.
Maybe, just maybe Simon means "code is disposable now", because some shortcut taker can spin up an apparent duplicate by coaxing and pleading with AI.
That is not a future worth participating in, that's intellectual begging death, because that will create an environment of worthless nonsense.