@It is ridiculous...
No, what's ridiculous is the concept that you might lay two cables to carry the traffic of one, thus providing 100% redundancy - these are expensive toys and can't be just left lying around not earning "just in case" they are needed one day.
Yes, there are a few 'self-healing ring' cables, such as Southern Cross, but even so, you have the choice of buying protected or non-protected capacity on it - you'll never guess which is the most expensive.
And for all you conspiracy theorists - I've seen the map of of where the cuts are - the 3 cables involved (SeaMeWe3 & 4 plus FLAG) all lie close together as they round the corner of Sicily.
The FLAG cable is heading around the coast to Palermo, SMW4 is passing by , heading towards France and a branch off SMW3 crosses these two heading into Mazara del Vallo - all three of these have been cut.
The map I'm looking at shows 17 cables landing on Sicily, all except 2 of them at that end of the island, so yes, it's real easy for a dragged anchor to cut more than one at a time.