Deltahotel's perception of risk is one I share and, I would suspect, so do many others.
Given that take-off and landing are by far the riskiest periods of flight, the bulk of the risk associated with flight - and the bulk of unease, if you are a nervous passenger - happens in a short time, and distance, at the beginning and end of the journey. For most of the travel time, most people will feel safe.
In a car, there are significant risks before you move off and, as soon as you gather any speed, those risks mushroom, and don't you know it. For most of the travel time, most people will be aware of the dangers of travelling by car.
Imagine travelling from Paris to St Petersburg by plane, and back by car: On the outbound leg, you've got one or two individual journeys (if you fly via Moscow) and you spend most of your time in well-managed airspace, shared by aircraft which will, at your altitude, have a couple of professionals at the pointy end. The leg back will have rather more individual journeys, on roads of varying quality shared with cars and drivers of indeterminate reliability. Oh, and 150 of those cars will carry the passengers you shared the flight out with.
Hopefully, you'll not perish on either leg. But which trip is likely to give you more near-misses?
In answer to the original question, I enjoy driving but I feel safer flying. I've got confidence in the airline experts; but confidence in other road-users...? Not even in myself, some days
NS