The owners surely think, or at least want us to think that it is very useful indeed, otherwise we'd see no point in burning through piles of investors cash to buy overpriced ram, storage, gpus, cpus, nics, secure the power to run it and then subsidise the users to use it.
I do think that transaction is wrong and it's going to bite them in the ass in the long term, but I don't have the money to outbid them for the power. I do get to see them crash and burn when the investors get impatient.
They’re not even saying they shouldn’t do it or that they’re not useful or not worth it but you Cannot logically say both “these things do not use a lot of power” and “we need to build more power plants to handle these things”
Edited to answer: The question has also been addressed by the same author as the article: USA spent a quarter century not building generators and that negligence has finally caught up to us, despite objectively heroic efficiency efforts on the part of the IT sector.