And just what vessels will deploy such sensors, and how many decades will it take to fully deploy such networks?
The Virginia class will be in use for many decades. Navy generally plans ship hulls for 30-50 years of active use. The enterprise cvn was in service for 50 years.
While such sensors may limit future sub combat options it is decades away. For one simple fact you still have to move attack assets into positions. Battleships disappeared due to two separate but equal reasons. The armor effectiveness/ weight versus gun size and firepower was drastically shifting in favor of the guns. And airplanes made those big honking guns worthless for antiship combat. As one or two bombs could still sink that battleship.
Sensors alone arent useful. You need weapons following those sensors. Those weapons can come from many sources but I bet sub's will be one of them.