Not all practitioners can jump to that highest level. They have to climb, step by step from the physical sphere to reach the spiritual sphere. If it is treated as exercise it is not the fault of yoga but of the practitioners.
B.K.S. IyengarI think many of my students have followed the advice I gave years ago, to give more than you take.
B.K.S. IyengarIf you open the armpits, the brain becomes light. You cannot brood or become depressed.
B.K.S. Iyengar