Even if we consider what they pay for colossus high (I've no idea, I haven't looked at the numbers), wouldn't this a bit be different from "investing in infrastructure"? They're not building the DC themselves, they're just renting, they can scale down to 0 anytime and not have pressure to recover costs, they don't have debt on the HW, etc.
At least from how it's described in the filing, it sounds like they're committed through 2029 on the deal with SpaceX. So they can't just pull out without a massive lawsuit from SpaceX.