Cars is a big part of it with Japan. I'd expect that even if all other things were equal Japanese consumers would prefer Japanese cars for the same reason a lot of American consumers prefer Japanese cars: companies like Toyota and Honda are really really good at cars.

I've got way more confidence that I can buy a newly released revision of a Honda and get a car that won't be a lemon and that I can keep running well for 20+ years if I wish with reasonable maintenance than I do for American car companies.

It's not an American worker vs Japanese worker thing. 70% of Hondas and 100% of Acuras sold in the US are built domestically and for the models that are made in both countries there is no significant difference in quality.

The American companies have been improving, to the point that when I decide to replace my nearly 20 year old (and still running great) Honda CR-V the Chevy Equinox EV will be a contender. The new Chevy Bolt will probably be a contender too, especially if they get it out before the federal tax credits go away. 10 years ago this would have not been the case.

Another part of it is the dollar is stronger than the yen. Japan has been accused of trying to keep the yen low but even if they are and they stopped it still will probably be weaker than the dollar.

The strong dollar isn't just a factor in trade with Japan. The dollar being the global reserve currency makes that a factor with nearly everyone else.

For agriculture and food products a lot of countries have stricter health and safety regulations. If an American company needs to put in extra work to make their exported products meet those standards that can make them more expensive and cut demand. The foreign food companies on the other hand are already making their products to meet their stricter domestic standard so it is no extra work to meet US standards.