I guess you didn't watch the videon in OP, because if you had, you'd know that they tried to buy the buildout and got quotes for 12-18 months, then decided to do it themselves instead.
That's the power of having a massive wallet. If you have unlimited money then buying the experts you need to just do it yourself is an option you have that others don't.
My point is that that is exactly what they DIDN'T do. They tried to buy the experts, but the experts would not have been fast enough. So they did it themselves.
Setting up a datacenter like that in such a short time is NOT a thing you can buy with money.
You have other people in this thread talking about how xAI offers massive salaries to top talent so it sounds like they do exactly that. Have the money to both hire experts and buy the equipment. I don't even know why this is a discussion, by virtue of doing what they did they needed to hire experts and buy equipment.