And in an automatic trans car , left foot is brake and right foot gas.

You can pretty much guarantee it went down like this:

Right foot on brake so the shifter unlocks. ( Remember, this was added to make sure the driver had a foot on brake before selecting a gear. )

Selected a gear for motion ( improper in this case )

Right foot moves from brake to gas.

Right foot presses gas, car is going in wrong direction.

Driver panics, presses harder with right foot in an attempt to " stop the car " but they forgot to lift off gas and move to brake.

Car travels a significant distance, driver claims " brakes failed ".

The above can all be avoided by dedicating right foot to gas and left to brake. Even if the driver forgets to lift gas foot, brake foot is trained to stop car. Given brakes are stronger than the engine , the brakes win.

I fully expect an emotional non logic driven outcry from some that 1 foot operation is better.