Right'O Dick!

You are right jlkonn. However one must be careful to define conditions, because side area distribution relative to the landing gear become important during takeoff and landing, while the wheels are on the ground.

But in the air, it doesn't matter whether it is a 747 or a Piper Cub, the only things that affect crab angle are the aircraft's true airspeed and direction, and wind speed and direction. Size of the airplane doesn't matter at all, nor does side area. If a 747 and a Cub were able to fly at the same speed (which of course they can't) in the same wind, they would have the same crab angle. Or a Piper Cub and the Goodyear Blimp. You get the idea.