My best guess is that Google realizes that something like GPT-4 is a far superior interface to interact with the world's information than search, and since most of Google's revenue comes from search, the handwriting is on the wall that Google's profitability will be completely destroyed in a few years once the world catches on.
MS seeems to have had that same paranoia with the bingified GPT-4. What I found most remarkable about it was how much worse it performed seemingly because it was incorporating the top n bing results into the interaction.
Obviously there are a lot of refinements to how a RAG or similar workflow might actually generate helpful queries and inform the AI behind the scenes with relevant high quality context.
I think GPT-4 probably does this to some extent today. So what is remarkable is how far behind Google (and even MS via it's bingified version) are from what OpenAI has already available for $20 per month.
Google started out free of spammy ads and has increasingly become more and more like the kind of ads everywhere in your face, spammy stuff that it replaced.
GPT-4 is such a refreshingly simple and to the point way to interact with information. This is antithetical to what funds Google's current massive business... namely ads that distract from what the user wanted in hopes of inspiring a transaction that can be linked to the ad via a massive surveillance network and behavioral profiling model.
I would not be surprised if within Google the product vision for the ultimate AI assistant is one that gently mentions various products and services as part of every interaction.