How does a seagull sized drone take out an Aegis class destroyer with all its advanced warning tech and defense systems? Damage maybe, but sinking?
Ever seen a video of a Phalanx CIWS in operation? Although a close in defense system and a last resort, they put out a spray of projectiles at 50 rounds per second. I doubt even a stealth drone would survive. I could be out of touch.
Hitting a dozen drones with a kenetic weapon is certainly possible. Hitting 200 or 1,000 would be impossible. A few dozen hitting radar and radio antenna or missile doors makes a mess of a ship’s capabilities to fight back. Small drones can punch holes in a ship, maybe not sink it, but still a mess.
I think the problem is whether the ships close in defenses could handle 100 or 200 hundred of these things attacking at the same time.
I agree that a small drone with a 1 or 2 pound warhead would do little damage to a ship but it would distract the crew while the enemy did something more sinister, like swarm the ship with fast boats at the same time.