IAS is not the speed of the air over the wing. TAS is the speed of the air over the wing.
Example: You are flying at 130,000 feet with only 3 air molacules per square centimeter at a TAS of 1,000 kts. You fly past a point in the air marked by a floating balloon.
With everything staying constant for one hour the balloon will be 1,000 nautical miles away and the whole time the airspeed indicator will have read 1 or 2 kts. The air molacules go over the wing at a velocity of a 1,000 kts (TAS) but the difference in pressure with only 3 molacules per square centimeter give a very low indication (IAS).