torque is the same across the system of gears, regardless of the lever, that’s why its Newton-meters. In engineering terms, you’re primarily concerned with the shear load on the axles or gears at their specific loading in the power transmission chain. Even with the CV joint or this uni-wheel, the force of engine braking and acceleration is going to put similar shear loads. In fact, I would think other similarly sized gears are subjected to similar loading in differential gearboxes and the actual transmission of most ICE engines. Making gears tough enough is easy. Even in the insane shock-loading they will see as a unsprung wheel assembly.

the whole point of this design is expressed in the video: efficiency.

It doesn’t matter what the longevity or durability of either design is, the problem is that a short axle produces high angles on a CV joint and lowers the power transmission efficiency of the CV joint dramatically. in order to pack the motors close to the wheel, and maintain a suspension system with enough travel, they have to use a different design to maintain the range and performance.