Completely different level of difficulty.

And be pedantic self-driving cars are not a solved problem. If you try driving a Tesla in autopilot and don't intervene when it makes mistakes you'll be in a wall within about 2 minutes.

Building data centres in space isn't just a technical problem, although it's a major technical problem, it's also an economic problem. Obviously yes it's physically possible to do it but there's no way of building a data centre in space for anything close to the price of just doing it on earth and with no other obvious advantage to it being in space there's no reason to do it.

It's the same reason we don't build a transatlantic railroad tunnel. Obviously it's technically possible it's just a very long tunnel, but it would be hella expensive.