The number of fatalities caused by cyclists is very small, but still non-zero. Here's some stats for New York City:
> In 2022 (the last full year for which there is data), three pedestrians were killed by cyclists, while 131 pedestrians and cyclists were killed by car and truck drivers. In that same year, 313 pedestrians were injured by cyclists, while 13,190 cyclists and pedestrians were injured by car and truck drivers.[0]
I've also seen numbers that there are about 600K cycling "trips" taken each day in NYC[1], versus 4 million cars per day driving in or through the city[2].
While those stats aren't measuring exactly the same thing, it appears that there's basically a 10x order of magnitude difference between the two forms of transportation. With that in mind, looking at the previous fatality numbers, bikes are still admittedly 4-5x safer than cars given equal use.
Even so, if we managed to get rid of 80-90% of motor vehicles, we would reach a point where in raw numbers people would be more likely to be injured or killed by bicycles than cars. At that point, I wonder if insurance would be required?
[0] https://nyc.streetsblog.org/2023/09/16/senior-struck-by-citi...
[1] https://www.nyc.gov/html/dot/html/bicyclists/cyclinginthecit...
[2] https://www.nydailynews.com/2019/03/21/why-not-charge-cars-t...