And kill their golden goose? Google makes more money the longer you spend on their ad-ridden search result pages. I don't doubt they'll make a question answering bot, but the real question is how they fund it (see edit above for my guess).
Someone will kill their golden goose sooner or later. It's better if they kill it themselves and silently replace it with something else.
But deploying something like that at scale not only means developing the consumer experience but also the ad placement platform that generates optimal revenue from it. It's not a thing to toss over the wall just because ChatGPT won some news cycles.
So why not keep people there by having an engaging chat bot? Could even refresh and add new context sensitive ads every time you ask something new.
Chat bots also can very naturally embed advertisement:
btw, I think you would really love to check this related product which according to many reviews can help with the problem you just asked me about.
Although clicking on them might not be quite as natural as clicking as part of search results, so still massive damage to the golden goose.