Perhaps be careful what you wish for.
The web's current advertising business model has a couple parts. A search engine shows an ad next to organic results and directs traffic to content creators who show ads (most of which happen to also be offered by the search engine company... what monopoly?).
The basic business model is that advertisers pay content producers and the platform takes a cut.
The search + display business model, together with the web making much easier ability to switch between content producers (primarily magazines and newspapers) blew apart the old print media model which was subscriptions + ads. Because of this, many publications struggled to get enough subscription revenue to keep the doors open and/or greatly consolidated. People don't want to pay for what they feel they can get for free. That's made advertising revenue paramount for most content producers, and leads to the nasty ad farms that I also detest.
The thing is that LLM search engines require content that is reasonably fresh, and the content producers have to make money somehow or they'll stop making content. Right now, LLM search engines are showing no ads whatsoever, and their responses are based on uhhh "uncompensated" content. They're also all operating at enormous losses right now, with "awesomeness" or "AGI" as the answer for how they will make money.
To replace the existing business model, the LLM search engines need to find a way to direct payments to content producers so that these people keep making content. And that's before the content producers win back payments for their "uncompensated" content. Maybe OpenAI and Claude think their fancy "reasoning agents" can synthesize the content and cut out the content producers. There may be some modest opportunities to do that, but I have a hard time believing they can cut out content producers altogether - nothing I've seen suggests that LLMs can translate meatspace into digital content in any way that makes sense, much less is interesting or compelling to a human audience.
That means that LLM search engines either need to get the advertisers to pay them directly and send the money downstream to content producers (e.g. through some form of licensing). Maybe they embed the display ads into the LLM results (a la paid search). Alternately - more realistically - they need vastly larger subscription revenues to license content and still make money. That in turn requires a large proportion of the people who used to be the free users in a freemium model to become paid subscribers.
Let's make the absolutely heroic assumption that OpenAI manages to capture paid subscribers at the same rate as Netflix (~75%). Netflix's revenues are ~$40B, while Google's are $350B - an order of magnitude difference. To get anywhere near the revenues that Google makes, the average OpenAI/Claude subscriber would need to pay some 10x what a Netflix subscriber does. I find it awfully hard to see who all those people paying $100+ a month are. 85% of Prime Video subscribers are ad-supported, and Prime Video is just an extension of Amazon's modestly profitable sales business and highly profitable cloud infrastructure business.
And that's without DeepSeek, LLaMa and everything else on HuggingFace competing with what OpenAI and Claude are producing.
It also means you should expect LLM search engines start inserting ads or even monetizing placement into responses pretty soon. But as long as the LLM response is the end of the query, it's hard to see how anyone wants to pay to be placed, or how paid content doesn't erode the idea the LLM "summarized what the internet says".
I find it hard to see an economic path forward for what OpenAI seems to want to do, much less plausible revenues to justify the hype and valuation.