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 a heat exchanger. You can't exchange heat with vacuum. You can only radiate heat into it.
Heat is going to limit the compute that can be done in a satellite data centre and radiative cooling solutions are going to massively increase weight. It makes far more sense to build data centers in the arctic.
Musk is up to something here. This could be another hyperloop (i.e. A distracting promise meant to sabotage competition). It could be a legal dodge. It could be a power grab. What it will not be is a useful source of computing power. Anyone who takes this venture seriously is probably going to be burned.
While personally I think it's another AI cash grab and he just wants to find some more customers for spacex, other thing is "you can't copyright infringe in space" so it might be perfect place to load that terabytes of stolen copyrighted material to train data sets, if some country suddenly decides corporation stealing copyright content is not okay any more
ISS radiators are huge 13.6x3.1 m. Each radiates 35 kW. So you need 3 of them to have your 100 kW target. They are also filled with gas that needs pumping so not exactly a passive system and as such can break down for a whole lot of reasons.
You also need to collect that power so you need about the same amount of power coming from solar panels. ISS solar array wings are 35x12 m and can generate about 31 kW of power. So we’ll need at least 3 of them. BTW each weighs a ton, a literal metric ton.
It hardly seems feasible. Huge infrastructure costs for small AI server rooms in space.