We are only grounded in systems of reputation & relationships. These systems will remain important as content becomes fully synthetic. I.e Linkedin, Google, Social networks already heavily depend on social and reputation graphs towards keeping spam at bay; if anything new ideas will be harder and harder to go viral as the social and reputational filters are forced to assume synthetic.
Maybe AI learns to leverage/buy endorsement "content" posts from your friends and colleagues like celebrity endorsements operate today (as personalized commercials/text become very low cost).
AI/people trying to drive value with AI will have to find ways to leverage social relationships to squeeze into relevance where content/ideas are very low cost.
so then if the world begins to prefer AI-generated content, any question you ask the internet will only show you AI-generated answers, which can only offer you answers based on its training set, and over time a system with no new inputs just ends up being static generated from static, albeit static which is convincing enough for a human to accept it.