Fundamentally, it's about product, and expectation shift. I am presently routinely having conversations, and for the first time in the history of the Internet, getting straight answers to moderately complex questions, and their follow-ups, in real time, from ChatGPT. Google's entire business model is "giving people pages on the Internet that might contain those answers", and some of those being paid for the user's clicks.
If I get the full answer, instantly, wrapped in 2 paragraphs of text.... where do the ads go? Editorials inside the answer? Why would I click them?