So, my thoughts on truth policing are split in two. Specifically, I believe that calling out actual inconsistencies or falsehoods in a story is valuable, as it helps fight against misinformation. At the same time, I feel that there is value in considering a story as a possibility, even if you have reason to doubt whether it actually happened.
To illustrate the first point, you might have a story where the author describes a conversation that happened after they claim to have left the area, with no explanation for how they found out what was said. Or they could make a claim about the law in a given area that is very obviously false. In both cases, I don’t think this reading should be expected to simply swallow what is told them without question. People should be allowed to read critically and verbalize specific issues they have with a story. This can both help to expose flaws in the story, and expose gaps in the knowledge of the reader. Because it is entirely possible that what one reader thinks is ‘implausible’ may actually be a common occurrence outside of that reader’s limited experience.
Which brings me to point two. Considering a story overall, even an implausible one, can be valuable, because it allows the readers to consider their position on the situation as a hypothetical. For example, I can have strong opinions on how wrong it is to skin a live animal, and those opinions and my reasoning for holding them will not weaken or become less valid, just because a given story of such a thing happening turns out to be false.
That second area is where I feel truth policing is most damaging, because in a lot of cases, those who indulge in it will try to claim that, since a given story is ‘obviously false’, that no discussion of the story should be done or taken seriously. It stifles discussion, rather than encouraging it.