Also, the function of a torque wrench isn't to apply a lot of a torque with less effort - that's the function of a torque multiplier.
A torque wrench is intended to apply a specific amount of torque to fasteners. Engineers and mechanics have specific torque values for threaded fasteners based on things like material, thread type, load types, and application, and a torque wrench is what we use to make sure that we hit those targets.