I'll do a write-up at some point. But the core drivers are launch cost, permitting delays for terrestrial datacentres and interest rates.
The balance is between, on one hand, the financing cost of the permiting delays against, on the other hand, the cost of launching radiators. (Chips are light. Solar panels without glass cladding are surprisingly light, too. The weight of an orbital datacenter is almost entirely in its radiator.)
The math high-level works with Starship (6 flights/year), 3+ year financing delays and a 10 kg/kW radeiator (assuming 6% financing cost). Of course, there are devils upon devils in the details. But directionally, we're seeing pushback against terrestrial datacenters. And from what I can tell, advanced heat pipes may be the unlock to get radiators down to 5 to 6 kg/kW, at which point I think even New Glenn's $300/kg projected prices become competitive.
It all goes out the window if launch costs don't come down, interest rates go above 10%, terrestrial datacenters start getting built quicker, or demand for this category of compute collapses.
> permitting delays for terrestrial datacentres
going down any time soon, or even being possible.
"Well, you didn't want a data centre in the field near your town, so instead we'll rain astrocentere debris across the western hemisphere and set off a Kessler syndrome cascade. Thank god we didn't have to wait for a permit."
Also, well before then, most of the bigger petrostates got together to create OPEC, raised prices enough to cause an economic crisis and stagflation. I don't doubt that big oil companies have bribed and/or SuperPACed and/or lobbied, but fact was, until the mid 2010s (exact year depending on where you live), renewables were more expensive than oil. Now PV and wind are both cheaper. But before renewables were cheaper they were a very hard sell, while "support oil and coal because power is critical" was a very easy sell.
Right now, space data centres are a hard sell even economically, but given most of the land area of the world isn't the USA, I can easily imagine the US not caring (because even what survives re-entry mostly won't end up in the US), while everyone else can care as much as they like but can't do anything about it (unless I'm right about a completely unrelated topic, which is that we're pretty close to ground-to-orbit laser weapons being viable).
Rates drive permitting costs. If rates are 1%, a 3-year delay is tolerable. If they’re 5%, that might crash your economics on its own.