Is that shot of the ship actually leaving or a stock pictrue? She hasn't got CIWS. Daring has it, but one would have thought that we'd not have deployed a Daring without fitting it. Phallanx was bought after Falklands war losses.
Or perhaps it is a message to Argentina - look, she is so good she doesn't need Phallanx to deal with your threat.
Its not as though we don't have enough spare Phallanx sets knocking round - 3 off Ark, and braces from Newcastle Glasgow, Cardiff, Nott, Exeter, Southampton, Manch, and Gloucester. That's around 20 units.