Did you actually read it?  TDEE differs seven fold between people due to differences in activity, not because of metabolic rates. "Total daily energy expenditure varies several-fold in humans, not due to variation in resting metabolic rate, diet-induced thermogenesis, or exercise thermogenesis, but rather, due to variations in nonexercise activity." People sitting on their fat asses all day is the reason for a low TDEE.  People that get up and move around burn more calories.  It has absolutely nothing to do with metabolism.