Dear Matt Visser,
Your fine essay was a joy to read; your less-than-worshipful analysis of quantum mechanics and QFT, a breath of fresh air. As you note, math is simply a way of codifying regularities. Assuming Kronecker's dictum, then the question of the non-mystical source of integers would appear the key question, and I argue that these arise directly from the physical logic of AND and NOT 'gates' at all levels of physical reality. As you say, prosaic. Your observations on the obfuscations of mystics, and the horrible price paid by trees, is quite astute.
I find your discussion of quantum pedagogy very well done and agree with all of your major points, including those concerning the uncertainty relation, 'tunneling', collapse of the wave function, and decoherence, and that these require new physical understanding, not new mathematics.
As for 'collapse of the wave function' implying no physical basis of the notion of memory, history, or trajectory, I hope you will find time to read my current essay, The Nature of Bell's Hidden Constraints, which analyzes a local model of spin based on the physics of particles in the Stern-Gerlach apparatus, entirely overlooked by Bell's oversimplified assumptions, and precluded by his "hidden" constraints.
Your observations on utility versus precision are extremely appropriate and those on the non-ontological, non-interpretive essence of "shut up and calculate" ring decidedly true.
Thank you for entering this insightful essay,
My best wishes,
Edwin Eugene Klingman