Not sure if relevant, but these are the survivors of the war.
It's more accurate to say these are the ships who survived to a peaceful decommissioning. The war had more survivors than just this, but they suffered a number of fates. From being victims of Crossroads Tests Able and Baker, to simply being scrapped due to being too outdated and unneeded.
(The full list of surviving IJN vessels would also include Nagato, Myoukou, Takao, Ushio, Kashima, and Junyou, among others)