The G3's protection and speed make more sense when read against a Far Eastern mission rather than a simple battleship comparison. These ships would probably have formed the cornerstone of an Eastern Fleet. They therefore needed to fight hostile battlecruisers while retaining the speed to avoid prolonged combat with true battleships. Their design was stronger against fast capital-ship opponents than the Lexington concept needed to be.
Notable Point · 13:13-15:57
Why the G3 design suited an Eastern Fleet mission
The G3 is interpreted as a distant-station capital ship able to defeat the fast forces most likely to hunt an Eastern Fleet.