The guy was obviously a jerk for yelling at you instead of asking if you were alright, but that doesn't make anything (other than your hurt feelings) his fault.

Life is full of risks. You have seen with your own eyes that cycling on a sidewalk has risks. I usually ride rail trails lately, but I rode 32 miles on roads Sunday, and I crashed because of a mistake I made involving a road hazard (no cars involved)... so, it was obviously a risk. However, it was still safer than riding on a sidewalk. I had cars give me plenty of room when they passed, and a few slowed down to stay behind me at a safe distance when I had to take the middle of the lane due to pot holes in the right side of the road. I even had someone in a car stop to make sure I was ok when I fell. I did use the sidewalk once... when the hill was too steep, and I walked for a while (you see what I did there? I emphasized walk...).

Don't get me wrong, over the years I have had issues with jerks on the road, and I have had a few close calls with inattentive drivers. My youngest brother died alone at the side of a road after the driver that hit him drove away... But, none of this makes cycling on sidewalks safe.

We do have to manage our risks... but that also means that you should consider the risk you saw with your own eyes, the one that the driver and I have pointed out to you.