Regardless of whether or not the implicit claim here is true (the claim being "all this spend won't produce an ROI"), the explicit claim here is nonsensical.
Of course the $1tn in capex has nothing to show for it! The spend has not happened yet! Of the spend that _has_ happened, most of the chips are not physically in data centers yet. Of the chips that _are_ in data centers, most of the models are not yet trained!
And of the models that _have_ been trained, many have clearly had a significant ROI. GPT-4 cost $100m, and OpenAI's revenue is now reported to be $3.4 billion a year.
Saying there's "little to show for it" is an absurd claim; the products are _printing_ cash! We beat the turing test! You can drive around in a self-driving car!
It's perfectly reasonable to say "where does the ROI come from when you spend $1tn on capex", but it's hard to argue against the success of the spend of the last generation of models.