Why faster sound in water would not transform naval warfare

How would navies change if the speed of sound in water increased by ten percent in 1923?

Not much; detection would become somewhat faster or longer-ranged, but both sides would gain the same acoustic advantage.

The hypothetical change applies to everyone using underwater sound in 1923. Signals would arrive sooner for both sides, with a modest increase in useful hearing range also assumed in the scenario. Each navy's opportunity to hear an opponent would be matched by the opponent's opportunity to hear it. On those assumptions, the change produces little relative advantage.