Then prove it? There have been actual studies that confirm this fact. You could also use the fact that google search has been losing market share steadily since 2023 and since search was supported on things like chatGPT as evidence it has been in decline. But, as I have in the past also said, I refuse to argue about this with google employees/devotees because there seems to be a fair amount of delusion involved.
For me, the user, it didn’t work. I got that from my own experience with it. You can point it at me and say it was my imagination, or i wasn’t “doing it right,” but that experience was absolutely true for me. If you care to you can even go back to my oldest posting history to see me complaining about it, and similarly people rushing in to defend it (very aggressively)