The textbook example of risk perception is flying vs driving, namely that flying is scary but safe and driving is dangerous. It's true the per mile or even per hour flight on airlines in the US is safer than driving. However, is is also true that far more people are afraid of flying? There are several reasons to believe the contrary:
Cliche: Since flying vs driving is such a well-used comparison, the message will get through to some people.
Close calls: Proportionally few people have had a close call on flying (though turbulence can feel like a close call). In driving, most people not only had close calls but have had crashes or know people who had serious car crashes.
Travel stress: Flying is very stressful (planning, security, jet lag, etc), so that can create many symptoms of fear (anxiety) or exacerbate an otherwise minor level of fear. We would like to separate the effect of fear itself from the other sources of angst.
Passive vs active: Many strategies for flying phobia (drugs, books, etc) rely on getting the mind away from the activity. This is impossible when driving.
Given all these caveats, is the fear of flying debilitating to more people than the fear of driving? "Debilitating" means how much it impacts quality of life. Taking a pill is less so than losing sleep the night before traveling, which in turn is less than not being able to fly at all.