I dunno about what Israel is doing, but a ship usually has enough power to fire 1 or 2 lasers at a time. It takes 10s of seconds to destroy a drone, and each drone stays in range for 1 or 2 minutes.
Or, that is their advertised capabilities. Countries that buy them usually complain that they don't work as well on practice.
Well, assume the advertised capabilities are realistic. Assume it takes 15 seconds to destroy a drone, the drone stays in range for 2 minutes, and you can fire on 2 drones at a time.
You can destroy 16 drones every 2 minutes. If you get attacked by 50 drones, you'll get 16-20 of them. Did that help you?