He does provide some evidence, although I'm not sure how much like statistics it is. Here: "Last week, the company parted ways with Vic Gundotra, a talented ex

He does provide some evidence, although I'm not sure how much like statistics it is. Here: "Last week, the company parted ways with Vic Gundotra, a talented executive who led Google+ through a thick fog of expectations. The company is also reported to be reassigning team members and sub-products (possibly Hangouts) to other business units. " He acknowledges that for some things like tech discussion G+ is doing fine. The argument is that, organizationally, Google itself is pivoting away from G+.