Let's get real - the US Navy is not going to advertise vulnerabilities, especially during a war. And what is left out of this report is how much we hobble ourselves during the wargames, to test the efficacy of various detection systems, in full and partial deployment. I hardly think these subs would be invisible in a full war scenario, with satellite gravimetric, IR & wake analysis and a/c sonobouys actively pinging to subs, surface ships and whatever land-based EM assets we have, all going full blast.
On the ther hand, it might be very useful to encourage Iran, North Korea, Venuzuela and the rest of the Tin Pot Gods to buy technology we actually can already track quite nicely (oops, did I give away the game?).
And as for the USS Ronald Reagan...