They have not, it is just that the financial crisis that hit Japan in the 80's forced them to go through bankruptcy earlier. At least in the case of Honda, Toyota, Mazda, Datsun (Nissan), Subaru, Mitsubishi and others.
BMW was rebuilt after WWII with US dollars (as was VW, Benz and others).
Almost (if not all) of the Japanese auto makers are/were owned in part by the big three.
If you look into the Wikipeda information of these makers you will find out things that will give you pause for thought on this subject.