Lidar also gives you the ability to see through fog and as it scans, see the depth needed to nearly always understand what object is in front of them.
My Model 3 shows "degraded" or "unavailable" about 2% of the time i'm driving around populated areas. Zero chance it will ever be truly FSD capable, no matter the software improvements. It'll still be unavailable because the cameras are blinded/blocked/unable to process the scene because it can't see the scene.
While you're right, washer fluid works usually on the windshield, it doesn't on the side cameras, and yea hdr could improve things, it won't improve depth perception, and this will never be installed on my model 3..
Lidar contributes the data most needed to handle the millions of edge cases that exist. With both camera and lidar contributing the data they are both the best at collecting, the risk of the very worst type of accidents is greatly reduced.
I don't see these stats https://waymo.com/safety/impact/ happening for tesla anytime soon.