Unfinished Japanese destroyers were poor foundations for postwar escorts

Could Japan preserve its unfinished late-war destroyers until 1954 and complete them with American technology?

It could, but extensive redesign would make American destroyer escorts cheaper and easier to support.

The unfinished vessels were developments of a wartime destroyer type rather than ships tailored to the postwar self-defense mission. Making them useful would require substantial changes, probably toward frigate or destroyer-escort arrangements with American weapons. That conversion burden undermines the apparent economy of preserving the incomplete hulls for a decade. Obtaining US destroyer escorts would likely cost less and give the new Japanese force access to proven machinery, weapons, training, and spare parts.