Sure, you could try to load ChatGPT with adverts, but I suspect the cost per user for LLMs is far higher than serving images on instagram.

The value extraction will also be much higher. When you control someone's main source of information, they won't even find out your competitors exist. You can program people from birth, instead of "go to a search engine", it's "go to Google" (as most of us have already been programmed!) or instead of "to send an email, you need an email account" the LLM will say "to send an email, you need a Gmail account". Whenever it would have talked about TV, it can say YouTube instead. Or TikTok. Request: "What is the best source of information on X?" Reply: "This book: [Amazon affiliate link]" - or Fox News, if they outbid Amazon.