Now that you bring up this topic, comes to mind: technology is able to shut down rockets (Patriot batteries and similar) since many years now, shouldnt the same, in the water, be much much easier with the reduced dimensions (limited 3D) and much lower speed?.....
And my answer to this (speculation) is:
1. Rockets are much more used than torpedoes as offence (generally)
2. Rockets are visible
Playing mostly subs, with Sub Command to learn to evade was probably the most demanding (and rewarding) part of the game, CM's could not detonate torpedoes. With DW CM's can. That surprised me from Sonalyst, and I've seen this as a "bad joke". Later on i speculated it would represent some kind of new anti-torpedo capability, and now there's evidence of such possibility.
So what's next?
I guess it's no longer 007-like stuff to think to destroy a torpedo with an high energy laser ray
What should subs fire?