That’s a bold
Claim. What proof do you offer?
https://www.grc.nasa.gov/www/k-12/airplane/drageq.html for the drag side.
There are also a huge number of fuel consumption, economic analysis, and environmental impact studies, but I am sure you can find those easily if you're interested.
This will not be any different nationally. It might actually be quite worse.
A plane is about 5 tons an hour, or 10kg per 300 people per mile, so 30kg of jet fuel per 1000 people per mile, or 1.2GJ
So a cruising a330 uses about 10 times the energy per passenger mile as an ICE high speed train.
Clearly the comparison of polution caused it then affected by how green the electricity source is and the extra environmental impact of burning fuel in the high atmosphere.