That was nearly true in the past, but now, submarines are targets in other ways, even from the air. That’s why friendly western nations have been trying to talk India and Taiwan out of being too sub-happy.
That is also very true.
I have another good friend who also served in the Navy servicing the P3 Orion. That platform along with satellite and other shipborne ASW technologies effectively decreases the efficacy of the submarine as the premier 'sword tip' of our stealth nuclear arsenal.