I don't remember if Fall also talked about this; I only read it once, and don't remember too many details. But Anathem definitely did; here's an HN comment quoting it: https://news.ycombinator.com/item?id=14554765
The first act of Fall explicitly takes place in a world polarized into micro-groups because AI chatbots generate so much content that it's impossible to determine what's true. It might even talk about the initial act that started the practice, I forget.
