Presumably it would require enormous startup capital?
I think they literally could get dump trucks full of cash.
I see no reason why they would of course.
Still as far as I understand and I fully admit that Is not a lot, OpenAI is running on a lot of MS cloud, so they would (probably ) ot be able to offer OpenAI² enough compuete in the near future.
I doubt anyone could, but if it became a need I am certain every at scale provider would be doing their upmost to win the business.