Why not just make it a tax directly and let those that drive faster than normal buy a plate to let them use the left most normal lane of travel? (Implicitly, r

Why not just make it a tax directly and let those that drive faster than normal buy a plate to let them use the left most normal lane of travel? (Implicitly, restricting everyone NOT using that plate). In fact, lets make robot drivers that go as fast and close as conditions safely allow... I think we're already on track for this actually.