The answers to both of those questions are pretty guarded trade secrets. Amazon and Google just to name a couple examples are very profitable companies and I would not bet on them investing all this money without real use cases where profit is likely. Amazon is adding thousands of new robots to their factories every year.
So your argument basically boils down to, the datacenter build out is not a waste of resources because if it was, these companies wouldn’t be building them.
I mean, your argument is that Google has had increasing revenue and profit for a decade, to the point that they have $400B in revenue + profit this year, and that they are going to lose money because they plan to spend $180B on capital projects for new data centers next year, because you know their business better than they do.