Some things are objectively measurable. Now, some party might claim to have measured and obtained one value when they have not (perhaps not having made a measur

Some things are objectively measurable. Now, some party might claim to have measured and obtained one value when they have not (perhaps not having made a measurement at all). But if a source’s claims are only* about the measurements they’ve made, and other parties can reasonably cheaply make the same measurements, and different parties measuring the thing in question will get results that agree, then it should be fairly doable for reputation to keep track of who is an honest source for these objectively measurements. Other claims are not so easily reducible to measurements that are cheap to independently verify. However, perhaps sometimes these other claims have implications about the measurable things, where the implication is straightforward to verify upon considering it. In this case, a fact checker could perhaps show that some claim contradicts some objectively measurable fact as reported by an independent organization which is broadly trusted to make and report on objectively measurable things which can reasonably cheaply be independently verified. Such a system would perhaps still have nothing to say about many claims we care about, but it could at least largely avoid that tower of fact checks for a restricted class of statements.