Fun thing about wikipedia is that if one person notices, they can correct it. [And someone's gonna bring up edit wars and blah blah blah disputed topics, but let's just focus on straightforward factual stuff here.]

Meanwhile in LLM-land, if an expert five thousand miles a way asked the same question you did last month, and noticed an error... it ain't getting fixed. LLMs get RL'd into things that look plausible for out-of-distribution questions. Not things that are correct. Looking plausible but non-factual is in some ways more insidious than a stupid-looking hallucination.