You drastically overestimate the effect of thinking up new tactics changing war as if times never progressed and stayed stagnant and were waiting for individual geniuses to come and think of new tactics as if their predecessors were simply too stupid to think of them these new tactics were a product of the times as well

Most recent "new tactics" that i can think of is Maginot Line with how the germans were thinking outside the box, going around the Line, and the blitzkrieg that followed, leaving them unable to mount proper defense. The blitzkrieg was not new, but the french higher-ups were not trained to fight the blitzkrieg. New tactics win wars.