[CaptainCrunch]

Couple of things.

during a collision the nukes wouldn't go off, but you could end up spreading nuclear materials over the bottom of the ocean if the reactors were damaged, or the missiles were damaged.

Ballistic missile submarines are built to be extremely quiet, their mission is to hide until they need to launch missiles. During the cold war an American Ballistic missile submarine was tracked by a soviet sub once for less then 10 minutes.

A well built boomer radiates less noise then the ocean around them, in essence they're a black hole of noise.

And in this case I can see where sonar is useless since no submarine actually radiates sonar energy, they tend to use passive sonar which is equivalent to putting a glass up against a wall and listening for noise.