I don't know why people are so fixated on heating as some kind of gotcha. If we already assumed magical 16km^2 solar array, then we can also assume matching size radiator, with heatpumps. If ISS can do it, then there is no technical issue with doing it on bigger scale. It "only" doesn't make any sense from financial viewpoint, terrestrial datacenters beat it in every way.
NVidia's recent support for warm (45 °C) water cooling for their new racks probably had more impact on price of compute than than space servers will ever have.