Fixed hydrophone defenses predate SOSUS and the world wars

Did the First World War Dover Barrage inspire the SOSUS network in the GIUK Gap?

Not directly, but SOSUS continued a much older practice of laying hydrophones to monitor key waters for ships and submarines.

SOSUS belongs to the long history of fixed hydrophone defenses, with a different arrangement from the Dover Barrage's mines and nets. Navies laid listening systems around important areas before both world wars to detect ships and submarines. The continuity lies in persistent acoustic surveillance of chokepoints, even though the surrounding weapons and network technology changed.