[lisper]

It turns out I was not as wrong as I thought. From the opening of the paper:

"...the term halting problem, the modern formulation of the problem, as well as the common self-referential proof of its undecidability, are all, strictly speaking, absent from Turing’s work. However, Turing does introduce the concept of an undecidable decision problem, proving that what he calls the circle-free problem is undecidable and subsequently also that what we call the symbol-printing problem, to decide if a given program will ever print a given symbol, is undecidable. This latter problem is easily seen to be computably equivalent to the halting problem and can arguably serve in diverse contexts and applications in place of the halting problem—they are easily translated to one another."

So I was basically correct, just wrong about a detail: it is the symbol-printing problem that is easily translated to the halting problem, not the circle-free problem. So I am going back to standing by my initial assessment: saying that Turing's paper was not about the halting problem because it doesn't actually use that exact phrase is like saying that the EPR paper was not about entanglement because it doesn't use that exact word.