4 electric motors on wheels is extremely simpler than 2 motors, mechanical differentials and couplings.

I actually helped a mechanical engineer to create a simulator for car dynamics in software.

Today's cars are over engineered mechanically in order to support and resist the forces and torques from the motor to the wheels.

When you put the motors in wheel you basically reduce the required rigidity and the weight of the car substantially.

You point out some disadvantage of the approach. The biggest disadvantage of all is that is not a proven technology, like 100 years old driveshaft. That means the company that commercializes it will eat all the risk, like what happens when people exposes the motor-wheels to wet surfaces and some part of it is damaged. The lawsuits could bankrupt even the biggest company.