I cant find when i subscribed to that particular belief in my ledger, it feels self-evident to me at this point. Whether it's true or not is mostly a semantic argument. You might personally define a beliefs "utility" to be strictly tied to its "objective truth" (or whatever epistemic ideal you assume), but the linked article posits a particular intersection of "rationality" and "utility" of beliefs (as far as I read it anyway). I found it agreeable and chose to share my musings on the topic.

I do not agree that the view is particularly post-modern, but since you called it first i guess i must concede. The point was not "all is subjective and nothing is true", rather "whether or not i take on this belief (or fact or whatever) presented to me is a function of the degree to which i understand it combined with my intuition of the ramifications of me holding this belief". We don't have truth-seeking minds, we have "value-" or "utility"-maximizing habits.

We understand things and we underestimate things. We prefer things and we reject things. Not always knowingly and sometimes intentionally.