"Pure fiction" and "no real world application" seem overly strong. Unless you are talking about individuals actually reaching complete agreement, in which case the point is surely true, but relatively trivial.

The interesting question (real world application) is surely how much more we should align our beliefs at the margin.

Also, whether there are any decent quality signals we can use to increase others' perceptions that we are Bayesian, which would then enable us to use each others' information more effectively.