Earlier quoted context omitted.
What's a hard case for vision? That's how our eyes work. LiDAR has problems with precipitation too.
Depth map extraction from vision in real time depends on accurate algorithmic merging of past frames, color gradients and motion vector extraction to come up with a 3D map of what's around the vehicle. Contrast this with LIDAR, which can present a depth map in real time by sending out an array of light pulses and timing how long they take to come back to the IP. Which method is more likely to have implementation erro…
However in the real world where the car/sensors gets dirty/wet, and the air is filled with snowflakes, raindrops, or mist it gets much more complicated.
Even if statistically better there's value to acting more like a human driver. After all the roads are filled with human controlled cars and any deviation from human norms because of weather(like wind, snow, rain, fog, and blown sand) cause problems.