Thanks to humans Richard Mallah, Risto Uuk, Max Tegmark, David Haussler, and Mark Brakel, for very useful commentary and feedback.
AI systems Gemini and Claude were used for some ideation, feedback, editing support, and citation chasing and checking. In the well-established standard of levels of AI involvement of creative works, this work would probably rate a 3.5/10. (There is in fact no such standard! But there should be.)