That's the number to beat, and even a single collision with an airplane would most likely make up the yearly allotment before we even get into "package falls on someone's head", "drone runs out of battery over the freeway", and all the other failure modes a drone has.
On the subject of vehicles-causing-accidents, it's possible delivery trucks trying to beat a deadline may be over-represented in statistics. Speeding, driving aggressively, parking all over the place. So there's that.
Planes fly at much higher altitudes than delivery drones, so the only collision worries would be near airports. The FAA already bans drones near airports and requires special authorization to fly a drone within miles of major airports. Even if you get approval, you can't exceed 400 feet above ground level.
If you're worried about delivery drones flying over neighborhoods, you should be even more worried about multi-ton delivery trucks barreling through places where kids play.
1. https://pix11.com/news/local-news/cyclist-fatally-struck-by-...
2. https://www.lehighvalleylive.com/traffic/2021/12/driver-of-f...
3. https://mynbc15.com/news/local/mobile-ups-driver-indicted-fo...
4. https://www.foxla.com/news/amazon-denying-responsibility-aft...
"The Air Commerce Act of May 20, 1926, is the cornerstone of the U.S. federal government's regulation of civil aviation. This landmark legislation was passed at the urging of the aviation industry, whose leaders believed the airplane could not reach its full commercial potential without federal action to improve and maintain safety standards. "
Maybe people were smarter in the '20s, maybe they were hoping for regulatory capture? Not sure, but obviously it's a good thing...
https://en.m.wikipedia.org/wiki/Federal_Aviation_Administrat...
Drones have to be specifically designed and manufactured to pass the FAA's certification program. We've all seen capable drones from Amazon's marketing, but does it please the FAA? A drone can't do the job until the FAA signs off on that make/model. It's not easy to do and requires developing a craft with all sorts of safety features.
Companies are making progress, and I think the most insightful videos to watch on the topic come from Zipline. They're already operating in Rwanda with support from their government. They have a streamlined service and make 100s of deliveries per day.