I am not exactly sure what is the exact reason, but I can guess the following: - High tariff imposed on electronics from non-japanese companies (protectionism) - Distributor <-> Maker mutual relationship to exclude cheaper alternative in order to maximize their profits and screw consumers

I highly doubt there would be some cultural bias - Japanese have no problem to work with Chinese when it is in their interest. I think they are probably very sensitive about letting Koreans take a bit on the Japanese market because they would wipe all the Japanese brands in no time if they did, at least for all TV and player systems.