Interesting. I can imagine a swarm of these little drones being unleashed to disperse a crowd for example. I don't see it being effective on a group of people dressed in military attire with helmets & goggles, but for crowds of normally dressed civilians it would be.

If the drones were programmed to target the eyes and face of a person at the minimum they could distract from their attention or interfere with eye / hand coordination.

For quite some time I've had the idea of using small drones or similar model aviation tech as a way to blind spying cameras that are out of reach, for example those used for red light cameras that issue tickets. Fortunately the trend appears for that use case to be fading away.