The CO2 factor is basically nothing, one rocket flight would be on the order of 10 commercial jet flights. The problem is soot from non-hydrolox launch vehicles, black carbon deposited directly into the upper atmosphere which apparently has a greater effect on warming than all of commercial aviation's CO2 emissions combined.
Starship is methalox so it's somewhat more ecological than the kerosene burning falcon, but with the increased launch capacity, the rate at which it can deliver stuff to orbit, practically all of which eventually burns up in the upper atmosphere when EoL will likely have much more of a polluting effect in total.
Starship is methalox so it's somewhat more ecological than the kerosene burning falcon, but with the increased launch capacity, the rate at which it can deliver stuff to orbit, practically all of which eventually burns up in the upper atmosphere when EoL will likely have much more of a polluting effect in total.