ttps://www.reddit.com/r/WarshipPorn/comments/1p6n6k3/the_usns_constellationclass_frigate_now/

荒れたスレもなかなか面白いな。
日本のイージスが安くて早いのには
安普請があるとかなんとか

The best source of this are some of the papers from the 1990s, when the USN was sending observers to Japanese shipyards to observe their practices. The USN was very impressed by the ability of the Japanese to build these ships at a lower price point and was eager to figure out what made this possible. Which, to be clear, goes far beyond simplified designs - there were genuinely better practices to be found. But likewise some of their approaches stand out for ways in which they differ to the U.S. approach to survivability.

The holy grail of this is the original report by Andrew B. Summers - Trip Report, Japanese Aegis Destroyer, Naval Sea Systems Command, NAVSEA 05D, March 18,1993

other sources that do contain some highlights from it.