this is already done. about a quarter of the big panels on the International Space Station are radiator panels.
they’re always aligned 90° away from the solar panels so the sunlight hits them edge-on and their faces are pointed towards empty space.
a satellite with data-center level servers on board would need an absurd amount of both solar panels and radiator panels, so many panels that it would need to orbit much higher than the ISS, because of trace atmospheric drag.
Nvidia is deep deep into the circular-financing scam - one recent example is they promised to provide two thirds of the money another company wants to pay for Nvidia chips. This demonstrates the prices are far far away from what real fair market prices should be, and that winners and losers are chosen in advance by negotiations between a few CEOs, not actual company performance. They’re unashamedly drawing attention to the fact it’s a bubble, and they’re still inflating it.