You won’t find churches teaching proper discernment, because if they did, they’d have to throw out half their doctrines that were derived through unreliable methods, and that no leader in church understands how such doctrines were (reliably) derived.
How can they know if their model answers are correct, if they cannot check the working of the experts from whom they got those Right Answers™ ?
Can the church leaders tell whether The Bible™ was accurately translated from Hebrew / Greek to English? Can they tell whether the theologians or pastors they’re learning from are using sound interpretational principles to produce their doctrines / sermons?
Of course not.
Churches are mostly run by religious fanatics who are grievously unaware of their own ignorance, yet revel in their unreliably obtained opinions on issues beyond their true discernment abilities.
The concept of a “bible”, usually defined as a book that magically (i.e. “divinely”, through processes that no human can verify) gets everything right, is itself highly suspect.
But if we understand sacred texts as time-tested tradition, that by virtue of being time-tested, are relatively more likely to be useful than something someone else just thought up on the spot, then we’d be on a better path, and stop imagining ourselves as having some special privileged information that other ordinary humans like us somehow fail to recognise.