Do you understand who protects the Carriers? Subs, Destroyers, and FRIGATES! The more surface protection available, the greater opportunity for successful OPS!
And we currently have over 60 guided missile destroyers with another dozen in the pipeline along with 20 guided missile cruisers to protect those carriers. That averages to almost 8 escorts per carrier. Currently a carrier strike force escort consists of a cruiser, a sub, and two, maybe three destroyers. I'd say the supply is adequate to the requirements.
The Navy built frigates during the Cold War because it was faced with the very real possibility of having to escort convoys filled with troops and supplies across the Atlantic in the face of a Soviet invasion of Europe. That threat no longer exists. All the Knox class frigates were retired long ago. The few remaining Perry class frigates have had their missiles removed and aren't used for much other than anti-drug patrols. Frigates don't factor in to the Navy's needs - cruisers and destroyers do. So why take funding away from the more capable ships just to buy less capable ones to fill the same job? Or worse, a job that no longer exists?