Per fuel/mile/cargo, aircraft are actually very efficient. Better than one or two people sitting in a gas powered car which is how most people drive. Of course, there aren’t transatlantic highways being driven across by armadas of single occupant cars, so the fuel usage is far higher for airplanes in such instances.

Let’s rephrase your position such that long-distance travel is bad for the environment regardless of the mode, period. There more energy efficient methods such as trains, especially local electric trains, but they are slow (unless you’re lucky enough to have a TGV or similar nearby).