The Iowa class and the Essex class are anomalies in the wider context of U.S. wartime production.
The U.S. had a vested interest in keeping the Philippines safe, as that was a major source of rubber and several citrus fruits used for everything from hygiene systems to car tires. More importantly the Philippines were a place for the U.S. to exert influence over southeast Asia, as previously they had been a U.S. territory between 1898 and 1934.
On the U.S. side the Great Depression was still completely in motion (it's one of the reasons why the U.S. agreed to grant the Philippines independence), and manufacturing had taken a major slump after 1937. The 1933 halt of reparations payments from the Weimar Republic once Hitler was pronounced Chancellor, 1935 automotive industry contraction, 1934 and 1936 dustbowl famine, and contraction of ship building and oceanliner travel in 1936 following changes to immigration policy meant that many factories were laying unused. American companies were actually trying to make manufacturing sales pitches to Nazi Germany starting in 1936 because they were fooled into believing Nazi Germany's economy was actually going to escape the Great Depression first. With over half the country out of work and every one out of three factories sitting unused, it was easy enough to hire enough people and fill enough factories to have the workforce and workspace required.
And more importantly, the tools back then were more universal and the parts were designed to be worked by those tools. A hydraulic press, bandsaw, and lathe were already within the factory most likely, and they were all that was needed to machine many parts. There weren't complex specialized dies or 8dof placement arms that could only make one specific thing. The SBD Dauntlesses were so quickly produced because you just needed an engine shipped in from Wright, a roller press, lathe, and a rivet gun for the most part. Meanwhile you look at what is necessary to create an F-35B, and there's such a complexity creep that it requires several different manufactories that are in different corners of the country and cannot be placed near eachother for logistical and environmental safety reasons.
The U.S. had a vested interest in keeping the Philippines safe, as that was a major source of rubber and several citrus fruits used for everything from hygiene systems to car tires. More importantly the Philippines were a place for the U.S. to exert influence over southeast Asia, as previously they had been a U.S. territory between 1898 and 1934.
On the U.S. side the Great Depression was still completely in motion (it's one of the reasons why the U.S. agreed to grant the Philippines independence), and manufacturing had taken a major slump after 1937. The 1933 halt of reparations payments from the Weimar Republic once Hitler was pronounced Chancellor, 1935 automotive industry contraction, 1934 and 1936 dustbowl famine, and contraction of ship building and oceanliner travel in 1936 following changes to immigration policy meant that many factories were laying unused. American companies were actually trying to make manufacturing sales pitches to Nazi Germany starting in 1936 because they were fooled into believing Nazi Germany's economy was actually going to escape the Great Depression first. With over half the country out of work and every one out of three factories sitting unused, it was easy enough to hire enough people and fill enough factories to have the workforce and workspace required.
And more importantly, the tools back then were more universal and the parts were designed to be worked by those tools. A hydraulic press, bandsaw, and lathe were already within the factory most likely, and they were all that was needed to machine many parts. There weren't complex specialized dies or 8dof placement arms that could only make one specific thing. The SBD Dauntlesses were so quickly produced because you just needed an engine shipped in from Wright, a roller press, lathe, and a rivet gun for the most part. Meanwhile you look at what is necessary to create an F-35B, and there's such a complexity creep that it requires several different manufactories that are in different corners of the country and cannot be placed near eachother for logistical and environmental safety reasons.