It won't pay off if LLMs efficiency gets good enough to make those data centers obsolete. It's a huge gamble.
What they can't do is the rug pull of pricing like Fable did, hoping for profitability while playing the "it's so super smart" card. It's very profitable, but customer will be very happy to leave for cheaper pasture and that's why the recent news about this or that cheaper chinese models make headlines.
Essentially, the rush now is "if I make it a boring profitable company I'm not worth a trillion AND i'm overshadowed that plays the singularity card even if they're bullshitting"