I work in a small startup doing innovative software/hardware products. Some of the most 'creative' work we have ever done as a team was when the power went out and we finally spent time workshopping what a particular thing should be like with a whiteboard and pieces of paper. That was a defining moment and what we came up with on that day is kind of what we have today.
Some of the best and most valuable insights in our process are captured in recorded IRL onsite sessions with our users. Humans put on a bit of a show when they're remotely connected and that just ruins the process because they just sort of withdraw after they say their bit. I have recordings that prove this - users spontaneously changing their minds or sharing more about how they really feel about something.
I would argue that the best creativity on a team occurs when there are actual meat-skeletons together in a room smelling each others' farts, interrupting each other, eating together, getting excited, getting pissed, whatever etc.
But you are absolutely correct that this is anecdotal and nebulous at best. In the article he mentions how this is better when the product is unclear and unformed yet.