Even a torsen diff, or similar helical/gear type limited slip diffs are "torque multiplying", they need a load on one wheel in order to send the "multiplied" load to the wheel with traction. Modern stability/traction systems equipped with helical diffs will apply the brake to the "free" wheel in order to provide a load to the mechanical diff. You can also apply the brakes yourself if you have a torsen diff but no electronics.

A clutch-based diff or some other type of locking diff would otherwise be required to solve the "wheel in the air" problem without applying an artificial load to the free wheel.