Why early US heavy cruisers suffered more

Why did early US heavy cruisers fare worse than wartime light cruisers?

Later cruiser forces had combat experience that the early heavy-cruiser formations lacked.

Much of the difference came from experience rather than cruiser category alone. Early heavy-cruiser crews and commands were not mentally or institutionally prepared for the realities exposed in the Solomons and at Tassafaronga, while later forces benefited from those lessons. Wartime light cruisers entered a fleet that had already paid heavily to learn how Japanese night fighting and torpedoes changed surface combat. Survival cannot be credited simply to armor or gun caliber when training, expectations, and accumulated combat practice had also changed.