Currently Falcon 9 is partially reusable, which is still more reusable than any other space launch system. One Falcon 9 launch uses 30,000 gallons of kerosene, which is half the fuel capacity of a Boeing 747. So these launches have got a pretty small ecological footprint already.

Once Starlink launches switch to Starship, they’ll be using methane fuel and fully-reusable spacecraft. SpaceX plans to produce the methane using solar power to run the Haber process, since they’ll be wanting to do that on Mars to refuel Starships there in the longer term, so that will be fully carbon-neutral at that point.

Starlink allows for Internet communication without having to lay down trans-oceanic cables or install other major infrastructure on the ground. So that reduces the environmental impact there as well.