It is pollution and it harms people. So in order to do things that are good we must harm others first (or after)?
How much pollution is okay? Why not argue for efficiency standards rather than bans?
Everything could be said to “harm people”. Banning travel could make some people depressed and who knows what that could lead to? Or it might lead to a less connected world and less familiarity with people in other places, and maybe makes wars more likely?