In fairness to the author, I think their point was that you take _several_ agents (not just one) and find a way to have them work like a team of 20 people. In the example, Sarah is trying to do the same job she did before, just marginally better.
It seemed to come down to the old 'just work better , faster, cheaper' , but that is dialed up to 11 now.
I realize the irony, of course, that this article is AI-generated but it provoked something close to an epiphany for me even so.