From the article:

""It's my view that there's no way you're going to get a return on that, because $8 trillion of capex means you need roughly $800 billion of profit just to pay for the interest," he said."

Right, THEY can't, but cloud providers potentially can. And there are probably other uses for everything not GPU/TPU for the Google's of the world. They are out way less than IBM which cannot monetize the space or build data centers efficiently like AWS and Google.