I understand that this is the standard story, but don't find it satisfactory; hence was presenting my own "deeper" explanation (which I still regard as tentative).
After all, based only on what you've said, a frequentist could also be a Bayesian! This doesn't seem right, or at least doesn't seem to account for the fact that there seems to be a controversy between "frequentists" on the one hand, and "Bayesians" on the other.
I don't see how a frequentist could Bayesian, to hold a Bayesian epistemology one would also have to adhere to a Bayesian theory of probability. Since frequentists don't hold such a theory that can not hold Bayesian epistemology.
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