I would not assume cooling has been worked out. Space is a vacuum. i.e. The lack-of-a-thing that makes a thermos great at keeping your drink hot. A satellite is, if nothing else, a fantastic thermos. A data center in space would necessarily rely completely on cooling by radiation, unlike a terrestrial data center that can make use of convection and conduction. You can't just pipe heat out into the atmosphere or build…
What in particular is wrong/misleading in the Starcloud whitepaper, then? https://starcloudinc.github.io/wp.pdf
"More efficient cooling architecture taking advantage of higher ΔT in space"
My bold claim: The cost of cooling will not be $0. The cost of launching that cooling into space will also not be $0. The cost of maintaining that mechanically complex cooling in space will not be $0.
They then throw in enough unrealistic calculations later in the "paper" to show that they thought about the actual cost at least a little bit. Apparently just enough to conclude that it's so massive there's no way they're going to list it in the table. Table 1 is pure fantasy.