Productivity For The Few: Morgan Stanley Finds Only A Dozen AI-Heavy Industries Now Generate 83% Of US Productivity Growth
Here is the bull case for AI in a nutshell: the trillions going into data centers will make the whole economy more productive, that productivity will pay for the capex (and the mountain of debt funding it), and the resulting disinflation will let the Fed relax. All of that depends on the gains spreading.
So far, they haven't.

