LEO satellite orbits decay. e.g. starlink sats are ~5 year lifespan. But assuming a higher, more stable orbit, how do you replace them? There will be tens of thousands of these orbital DCs, so not really feasible to go to each one to replace some chips.

Or alternatively I guess a few massive ones, but those would need to be truly massive to accommodate the solar panels and radiator fins required.

We already re-supply ISS. IDK how much of it can be done autonomously, but no doubt we'll do hella lot more in future if space economy grows.

For orbits, those can and will be raised if it makes economical sense.

We re-supply a single ISS. If all of this compute is in a single DC the solar panels and radiator fins will be the size of a small state.