Yikes! If so, he could have saved a lotta money by purchasing 4090s instead of spot pricing. Last time I did the math, break even between buying and renting was only 3 months. I wonder if the search took a lot longer than he anticipated
If you're talking about $2M worth of 4090s you have to concern yourself not only with putting them in hosts, but also with adequate space, power distribution, cooling, and networking. You have to figure out how to gracefully handle hardware failures. You have to install operating systems, or at least come up with some mechanism to deploy automatically. And you just straight up have to supply labor to get 1000+ of these things plugged in.
All that before you can get even get to the "fun part". If you're a multi-millionaire you might be willing to just pay the spot price premium.