Humans on the aggregate can definitely get better, that's why Norway has 2.14 / 100k traffic-related deaths per year and the United States has 12.84 / 100k.
Norwegians drive half as much. Even if we ignore the other components of the gap, closing that 50% will require rebuilding 300000 square km of urban sprawl into dense urban centers with good public transit. It's a nice thought, but my money is on the robots.
The "human drivers are shit" problem kills a million people every year. Solving it is good. If we let the great be the enemy of the good we will never fix anything.