I get skepticism that orbital datacenters will make sense economically. It would not surprise me if they never happen.

But if they made economic sense, then they would be much more environmentally friendly. On CO2 emissions, we're talking about a factor of 37. That's not a small amount. Even a factor of 10 would be a major issue multiplied by terawatts of power. Sure, maybe Earth-bound energy gets cleaner, but it's not going to get 10 times cleaner before 2036.