Internet is already full of bullshit SEO content. Sometimes written by humans, and quite often by bots. For years now. What's coming is an arms race between different content generating AIs and search/answer AIs.
One of two things will be true. Either:
If it’s 2, then we’ll have to develop AI that detects AI-generated content. But if you have the machine that can detect whether content is in the category that helps it improve, then you have an algorithm for generating content that helps it improve.
So either 1 is true, or AI will plateau, or it will be trained only on networks where confirmed humans are the only ones participating.