They didn’t deny people’s brains produce thoughts all the time. The point is being painfully aware of them, having so many/with such intensity you don’t recall any “quiet” moments. Each person’s subjective experience is the point. Other people can experience more calm and silence, and it’s accurate as their personal experience. The fact they can’t tell that they have a constant stream of consciousness going on is the point.

They still offer an alternative on their noai subdomain