A falcon 9 launch burns roughly 260 metric tons of liquid oxygen [1]. CO2 is 1.375 times the weight of O2, so assuming complete all that oxygen turns into CO2 we're looking at 357 metric tons of CO2 (which is an exaggeration, because a good portion of it turns into H2O instead... but the H2O is actually slightly concerning because it's in the upper atmosphere... so whatever).
Canada wants it's Carbon tax to reach $170 CAD per ton by 2030, which seems to be considered a pretty agressive carbon tax [2]. At this rate the fuel burnt in flight would cost a whopping 61 thousand dollars CAD... or 48K USD. On a multi million dollar launch.
Furthermore, SpaceX’s upcoming rocket can be carbon-neutral since it burns methane, which can be extracted from the earth’s atmosphere.