That's his point, we _know_ this. People can already use OpenAI as a replacement for Google search and people are already doing this. You might not think this is a good thing yadda yadda go to the library, but we already know that chat bots are here to stay.
There is a huge spectrum between "here to stay" and "changing everything". On another note, I think if the people arguing here would work out quantitative predictions, they would find that a not insignificant part of the "disagreement" about how big we should expect this to really be is in the framing.