It seems like an obvious thing on the surface, but I've already noticed that when asked questions on LLM usage (eg building RAG pipelines and whatnot), ChatGPT will exclusively refer you to OpenAI products.
It has always been easy to imagine how advertising could destroy the integrity of LLM's. I can guarantee that there will be companies unable to resist the temporary cash flows from it. Those models will destroy their reputation in no time.
https://www.washingtonpost.com/technology/2025/04/17/llm-poi...
One major problem is the payment mechanism. The nature of LLMs means you just can't really know or force it to spit out ad garbage in a predictable manor. That'll make it really tricky for an advertiser to want to invest in your LLM advertising (beyond being able to sell the fact that they are an AI ad service).
Another is going to be regulations. How can you be sure to properly highlight "sponsored" content in the middle of an AI hallucination? These LLM companies run a very real risk of running a fowl of FTC rules.
You certainly can with middleware on inference.