Why is the world willing to move on after Nazi but not Japanese occupation?

The reason is simple. The Germans apologized with utmost sincerity for the atrocities committed by the Nazis. When you visit any museum that displays Nazi's history and crimes, you can see a true account of the past. The Germans do not whitewash their acrimonious past.

https://www.washingtonpost.com/news/worldviews/wp/2015/08/13/germany-won-respect-by-addressing-its-world-war-ii-crimes-japan-not-so-much/

For Japan, the Japanese tried to whitewash their unglamorous past starting with their school textbooks and also protested against the Unesco Nanjing Massacre listing. Why? This makes it hard for Japan to deny the Nanjing Massacre when it is listed under the Unesco.

https://www.theguardian.com/world/2015/oct/13/japan-threatens-to-halt-unesco-funding-over-nanjing-listing

Not only does Japan government whitewash its history, it also worships the war criminals in the yasukuni shrine. This is akin to extolling their ruthless actions during WW2 especially when the government officials visit the shrine on an annual basis.

The world will never forgive Japan and move on because of insincere apology. The world cannot reconcile Japan's insincere verbal apology with regular yasukuni shrine visits and history whitewashes.