Most knowledge sources don't make up totally fictional citations to nonexistent sources. Or, if they do, nobody uses them for anything serious. Even Wikipedia citations will get removed if they point to URLs that never existed.
if we focus on the best sources, even in studies a lot of research can't be replicated, and if we focus on te most common ones like newspapers and tv, I'd say most of it is made up or might as well be
But I'm not talking about it just being wrong, I'm talking about it citing webpages and books that don't exist and never did[0]. If Wikipedia regularly had that sort of quality issue people just wouldn't use it. There's a threshold below which something stops being useful.
[0] Bloggs, Joe. "ChatGPT just makes stuff up". Nature, vol 123, 2022, pp 123-321. Wiley Online Library, https://doi.org/10.1111/111/111
