> Err...have you actually asked someone to get into a Cessna?

Yes? In practice once you convince them to get into the plane the only real issue in the air for those new to flying is air sickness.

Also fun fact a good number of pilots claim to have a fear of heights (never met one irl except online in aviation forums).

If you are in aviation/aerospace, don't be afraid to share the joy of flying. There's nothing quite like cruising at 90-100 knots @ 3000-4000ft AGL on a nice clear day.