Why are tall people at an evolutionary advantage/ healthier?

tall people are apparently viewed as more attractive, studies show that they are healthier, there are correlations between intelligence and height, ect. Obviously being tall is advantageous. Most tall people I see are weak, gangly, and uncoordinated. My friend is 6'5" and breaks bones very easily, he sucks at sports and is clearly weaker than most. He sucks at fighting too. Ive seen this with most tall people. It just seems that their larger frame is weak and stretched out and awkward. How is this an advantage?