This is like the arguments that C programmers just need to be more careful about errors. We know that people make mistakes, get distracted, and get older. Real engineering is about designing systems which work well in actual conditions, not some unrealistic ideal case assuming perfect conditions.

It’s also simply wrong: in California, I had to show use of turn signals – not anything else – and no other place I’ve driven since has ever made me pass a test again. Assuming that everyone reads the manual and practices with every new vehicle is unrealistic, so you’re looking at potentially half-century lags between what’s tested and what people are driving.