Airplanes are pretty common and don't account for much of the overall pollution. According to the EPA, transport accounts for 29% of total emissions, and of that, only 10% are airplanes. On the other hand 75% comes from cars and trucks.

If rockets became commonplace, they would most like replace leisure travel on airplanes and would eliminate car traffic once you arrive at your destination. The CO2 emission of the current SpaceX rockets is about the same as one full plane across the Atlantic. So if you could take 300 people in one launch, you'd probably take those 300 people away from an airplane flight and it would actually be better for the planet.

Have you considered the secondary effects from higher altitude? Planes have less emissions per passenger and kilometer than cars but the advantage is completely cancelled by secondary effects because of the high altitude.

https://www.bbc.com/news/science-environment-49349566

And rockets need special start locations to reduce the amount of fuel to reach the desired altitude, additionally the landing places must be way outside of your flight location, so you need extra transportation to your destination too.

How do rockets eliminate car traffic at the destination? Every proposal for rocket transport I have seen basically puts an airport outside of town, so the traffic is a wash, no?

When I arrive in space I don't need a car to get around, and even if I did, the pollution wouldn't affect the Earth. :)

Ohh, ha! I thought you meant replacing flights directly to Earth destinations. So instead of taking a 787 from Seattle to Taipei I would take a Starship.

Yes, there are environmental benefits to putting the actual destination in space, I hadn’t really considered that.