How do you know they chose to not fly _because of the TSA_? What if it's the opposite and they chose not to fly out of (statistically ridiculous) fear of terrorism?
I don't fly because of the TSA. I have zero fear of terrorism on my flight.
Obviously you/we don't represent the majority. GP is a valid point, in that without polling the people who are choosing to drive [0], we don't know their actual motivation.
[0] Don't give the thugs any ideas
If the increase in driving happened at the same time as an increase in TSA, then you don't need polling.
Correlation is not causation. For example (as was said), an alternative mechanism is that someone actually believes the scaremongering narrative broadcast on TV, and is choosing driving to avoid the bogeyman^Wterrorists.