I have sometimes wondered about that (I guess I have too much time on my hands).
One approach to RHD cars that appeals to the engineering mind is simply to flip the blueprints, so the gear pattern and pedal layouts would be mirror imaged about the centerline. Come to think of it, maybe the gauge faces and and legends should be, too. ≤}B^)
I guess ergonomics does enter into it at some point, though, spoiling the sweet symmetry of the strictly engineering approach.