I think the point that the officer was making to me on the frigate, was that the best defense against that sort of thing is to have other very large steel objects in the immediate area.
In the Falklands, the antiship missiles were fired at long ranges, a couple of hundred miles,towards targets unseen but located in general by coordinates from airborne and ground radar. In the attack against Sheffield, the pilots were rather more successful, probably because they had practiced against their two own destroyers of the same class. In the attack on Invincible, one missed and the other hit a big cargo ship, unless you want to believe some sources that claim the missile hit the carrier and the British covered it up by sinking Atlantic Conveyor themselves.
But after flying for 15 minutes or so, the AM39 only had a couple of seconds to find a target, looking for a big radar hit.
Granted that's old technology, but if I were an Admiral and deployed a super carrier, I'd probably surround her with empty container ships. Hey, they are cheap.