Ichi-Go and the cost of Japanese strategic disunity

What did Operation Ichi-Go reveal about Japanese Army-Navy strategy late in the war?

Japan could not effectively pursue its southern maritime strategy while the services allocated resources independently; a coherent island-defence and naval effort required joint priorities.

Once Japan chose the southern resource area and an island strategy, Army and Navy resources had to serve the same plan; otherwise the fleet could not sustain the wider war. The services instead pursued rival priorities and even built parallel landing ships and other capabilities. More troops and material on contested islands could have made American amphibious operations slower and more costly. The Americans bypassed many positions but still had to capture some, and stronger garrisons on those objectives could have consumed more assault forces and delayed later advances. This was an attritional maritime war: time bought at one island could be used to reinforce another.