That's the whole shape of AI for consumer-facing functions like this. It's not superior to the previous experience, but huge sunk costs and a misguided belief it's the "next thing" is leading companies to try to force the issue. It's the Apple removing the headphone jack of the modern Internet. A change for the worse that we'll all have to find ways to work around.
There's a measure of game theory here too. If Google didn't hop on the AI train, people would use ChatGPT or Claude to fill the Internet with slop and 10-blue-links Google would cease working anyway (which it kinda has already). So their only option is to hop on the AI train and disrupt themselves, lest they be disrupted by others.
It's very much a Prisoner's Dilemma. Legacy search and the open Internet was an equilibrium that only existed while the majority of people co-operated. Once you allow an individual actor the ability to create large chunks of the Internet, it dies. Your only option is to be that individual actor.
Beyond the AI expenses, prompting captures more information from the consumer that keyword search. I assume they can take a lot of advantage from this and a new generation of ad engines is near the corner.
Google famously dragged on development of Glass for more than a decade stubbornly failing to admit that nobody wants to look like a cyborg the entire time only to be swept aside by Meta when they built a device that was glasses first with some recording and interactions built in.
If their leadership has an itch they'll scratch it until it's raw.