Russia uses a similar system, the Kashtan CIWS. This article (https://www.bbc.com/news/world-europe-61103927) indicates that the Moskva did have one installed, though I don’t know why it didn’t help in this case.
Drones are reported to have been used to harass the vessel and keep its air defences distracted before the missiles were fired from a hidden battery near Odessa. At least two of the missiles are then reported to have struck the ship – causing a massive explosion and inferno as they are believed to have detonated one of Moskova’s exposed deckside missile tubes.
https://www.news.com.au/world/europe/sneaky-way-ukraine-dist...