(Except the claim as stated isn't always in the source anyway. Best to check.)
> The way we determine reliability is typically based on the reputation for editorial oversight, and for factchecking and corrections. For example, if you have a reference book that is published by a reputable publisher that has an editorial board and that has edited the book for accuracy, if you know of a newspaper that has, again, an editorial team that is reviewing articles and issuing corrections if there are any errors, those are probably reliable sources.
https://en.m.wikipedia.org/wiki/Wikipedia:Reliable_sources/P...
Those voters (with the exception if bad actors) are working on the basis of "factual circumstances", which they debate extensively before voting.
And most LLMs probably have Wikipedia as a significant part of their training corpus, so there is a big ouroboros issue too.