SEO garbage is such a problem these days that, if I were Google, more than using AI as a new frontend for search, I'd be trying to find a way to use it to defeat SEO.
SEO for AI will be worse. Their output is a probabilistic distribution conditioned on the text is has read, so you can place text that heavily biases the output. Usually figuring out what this is can be kind of hard, but since OpenAI lets you query GPT-4 for credits, you can just mine what these special phrases are.