That's entirely true at Bismarck Sea.    However, slow unarmored transports and destroyers limited by the troopship's performance are far different than maneuvering warships making 30 knots.    Repulse, with no fighter cover, threaded the wakes of nearly 20 torpedoes before she took meaningful hits.

Also land-based heavy and medium bombers had a terrible track record against any kind of Japanese shipping, until they drastically changed tactics with low level skip bombing  and noses packed full of machine guns instead of windows and bombsights.