I would also list Hollywood as a big reason. There are countless Hollywood films, and there have also been TV mini-series depicting the Holocaust. I won't go into the obvious reasons why. Of course, there are countless, probably even more, Chinese, Korean, etc., movies depicting the atrocities committed by Imperial Japanese troops, but of course these aren't so well-known nor as popular in the West.

FWIW, I think the Japanese government should have made a formal apology a long time ago, and done its best to make restitutions to survivors. But this continuing to blame Japanese people as a whole by some (many) in Asia is really tired and played out. NO country or group has clean hands in regards to committing atrocities and whitewashing/denying it.