The idea of Quantum Bayesianism, as I understand it having read six pages of C. Fuchs “QBism, the Perimeter of Quantum Bayesianism“, is to declare the quantum state to be a (misleading) expression of one’s own beliefs about the probabilities of a set of measurements. Meaning that the probabilities of quantum mechanics are personal Bayesian probabilities: reflections of one’s own best understanding of the system and the available information. As Fuchs describes it, there is non-locality here if there is some preferred state to represent the system, one that is always more correct than any other. There seems to be more than this, but I haven’t gotten to it yet.
However, it seems clear that the condition of the end implies that objective reality is unknowable, and there is an absolute limit to the accuracy by which we can know the quantum probabilities. For else there naturally exists a best state, and it’s all been a circular exercise.
We’ll see how the story continues…