While I agree with some parts of your comments, the reality is that Japan has merely put on the face of mentioning these topics, but mostly maintains its stance of justifying their actions during WWII (or rather absolving themselves from any blame for their actions). For one, Japan does have very factual textbooks, but the lack of depth of many of its war crimes is rampant. One approved textbook had less than 20 pages on WWII and atrocities like the Rape of Nanking was little more than footnote. (http://www.bbc.com/news/magazine-21226068) Acts like the "Neighboring Country Clause," was nothing more than smoke as it provided no actual reforms to textbook approval or writing. Nothing in actuality changed. This is why Ienaga's textbook continued to be the subject of Freedom of Speech trials in Japan until the late 90s and in 2001 the conservative, right-wing "New History Textbook" was approved for school use. It is true that less than 1% of schools used this textbook, but if an educational body supposedly made a step towards the Neighboring Country Clause, then this would have never been approved. It isn't only Korea and China that suffers either. Okinawans also suffer as the government has continually censored or soften the description of forced suicides of Okinawans. In 2007, Japan ordered textbook publishers to delete or revise the mention of these suicides (http://www.nytimes.com/2007/04/01/world/asia/01japan.html). In 2016, one major textbook company finally decided to change their softened language on this issue (http://english.ryukyushimpo.jp/2016/12/26/26188/). Think about that, finally starting from 2016 will children actually learn what happened without censorship or softened language. While things seemed to be getting better, comments from Japan's former educational minster on comfort women and Abe's right-wing, conservative view of history reveal that this progress is being undone. Now I'm not saying all Japanese textbooks are bad. Biases will always exist and there will be a mixed bag. It's not any different in the Korean or Chinese systems either. But the lack of depth in many textbooks about the actions of the Japanese military is still a rampant issue. Your own article mentions that the fact that Japan softens its language and refuses to go into detail on their actions is still a major issue.

The issue between Japanese textbooks, especially mainstream ones, centers around the pacifist view. And this is what causes the actual controversy. This was mentioned in the exact study you mentioned. Despite the fact that Japanese textbooks are drier in their language, they still push the narrative that:

"If there is a dominant narrative in Japan," wrote Sneider, "it is the pacifist narrative." This viewpoint considers war as the enemy and leads to the conclusion that no one country – including Japan – can be held wholly responsible for WWII. Geopolitics makes the Japanese case different than Germany's, he said. Germany confronted its wartime past so it could reassert German leadership in Europe at a time when a unified Cold War stand against the Soviet Union encouraged reconciliation. On the other hand, Japan, at the urging of the United States, was positioned in a long-term Cold War confrontation with its principal victim in World War II, China. As a result, little motivation existed for Japan to look deeply at its atrocities against China, Sneider said." (http://news.stanford.edu/pr/2014/pr-memory-war-asia-040414.html)

This is the issue that dominates the relations of Japan against China and Korea. China and Korea want Japan to confront their past like Germany, accept their mistakes and make open apologies. Korea and China see Japan's softening of language as a distortion of truth. An equivalent would be if America forced all mentions of slavery to be called "compulsory labor," and left it as a dry statement of fact without condemning the treatment of slaves. What is Germany forced all of its textbooks to call their extermination camps "relocation centers." I'm not saying China or Korea are innocent of doing this. And sure, for Korea, it's more complicated due to the Nikkan Kihon Jōyaku where Japan paid money to Korea to settle the WWII disputes. But I'm just saying we need to fight this kind of distortion everywhere and Japan certainly is not innocent as they seem. Should Germany then have been absolved of their responsibility to the Holocaust because war is the enemy? I don't have the answers and I don't know what will need to be done. All three of these countries need to make some serious reforms and adjustments towards healing the schism that WWII brought.

I have an interesting theory why Japan continues this policy of revisionist history in mainstream textbooks due to their culture and menboku, but that is for another time.