This is an arms race, except the second player hasn’t shown up to the game yet.
The regulators must sponsor fact checking AIs. Bing Chat is a start. Alas, the regulator’s as usual have no idea what’s going on, except this time the rate of progress is so large even technologists can’t see further than a year out. Scary times.
Wikipedia has multiple controls that facilitate quality and authenticity of content, but a lot of them break down in the face of synthetically polluted generated info.
The cost of engaging with the editorial process drops to functionally zero as sock-puppets are trivial to spin up that are near-human in quality. Run 50 of those for n-months and only then use them in a coordinated attack on an entrenched entry. Citations don't help because they rely on the knowledge-graph, and this pollution will spread along it.
Really what's left are bespoke sources that are verifiably associated with a real individual/entity who has some external trust that their information is authentic, which is tough when they're necessarily consuming information that's likely polluted by proxy.