Of course there were efforts to 'work out' the steel mills problems, but it was easier to just close them and move operations to the new automated plants elsewhere. Some workers were given the option to relocate, others were not. This was a very rapid transition that left small towns almost empty of industry. I have pictures of the empty plants and big parking lots along the Monongahela river from Clairton to Pittsburgh. Among others, the worlds largest seamless tube mill closed rather abruptly after a large expansion and modernization. They did not move elsewhere AFAIK, the Japanese industry took over.
As far as Japan is concerned, where did the money to rebuild come from? The USA.
As for the caste system, it still exists. The system is built into Japanese and you see it when the people bow and still prostrate themselves on the street when the Emperor's limousine drives by in downtown Tokyo. At least that is what took place when Hirohito was alive, and when I last visited Tokyo.
I have seen the Hachioji steel mills and the Konishiroku Photo plant next to them with my own eyes. The mills were flattened during the bombing of Japan and rebuilt from nothing afterwards with our financing.
Japanese plants in the US are productive for one reason. High levels of automation reduce the levels of manpower needed to run them. Many parts are made in Japan and the final assembly only takes place in the US. Therefore the savings is still part of the equation.
In addition, it is not unknown for Japanese laborers to work 24 hour shifts with a cot next to the production line for naps. Their wives or gfs bring in fresh clothing and food. They had a saying that translates loosely 'we have to do this to stay ahead of the US'.
Deming had a great influence on improving Japanese quality control. That was his major reason for assisting them.
I came upon a group of Japanese engineers at COMDEX once looking at a computer display. They blocked the aisle and were talking. They said approximately "hey this is good and it was made in America". It made me feel rather sad. BTW, the comparable Japanese product was good, came out a year later or so by reverse engineering, and was less expensive by a rather large margin.
Just to stay on-topic, much Fuji film and paper is coated in Japan and the master rolls are slit and chopped here in the US. Some of the accrued advantage is shipping a Japanese product from the US to other parts of the world, as trade restrictions between the US and the rest of the world is often less than between Japan and the rest of the world (AFAIK and remember - it has been a few years since I researched this so things may have changed).