CWIS have an extremely low radar horizon - most contemporary AShM weapons fly extremely close to the water, sometimes even lower than the bow of a suicide vessel. It's very feasible for such a weapon to neutralize a USV in terminal attack.
> Watching the Russian fleet "deal with" Ukranian drone boats
Most of the successes I've seen with Ukraine's drones are against unarmed targets. They had great success using USVs to attack oil rigs in Crimea and Mi-8s with very weak countermeasures.
This isn't to say that USVs are useless against the Russian Navy proper, but even Russia has weapons intended to pick off surface combatants at a standoff range. I suspect we don't hear more success stories because they're at least partially capable of defending against them.
> Watching the Russian fleet "deal with" Ukranian drone boats
Most of the successes I've seen with Ukraine's drones are against unarmed targets. They had great success using USVs to attack oil rigs in Crimea and Mi-8s with very weak countermeasures.
This isn't to say that USVs are useless against the Russian Navy proper, but even Russia has weapons intended to pick off surface combatants at a standoff range. I suspect we don't hear more success stories because they're at least partially capable of defending against them.