The complaints have come largely from historians who believe that Taiwan is a part of China. The research of many current scholars shows quite clearly that Taiwan has never been a part of China except for 1945 to 1949 during the Chinese Civil War when the Chinese colonial regime occupied Taiwan and slaughtered many Taiwanese.
Actually Taiwan was not part of China then either. Taiwan had been handed over for administration jointly by the US and the ROC under the rubric of the wartime allies. Chiang derived his control of Taiwan from MacArthur's directive, not because he was dictator of part of China. This was repeatedly emphasized by the US during the 40s and 50s -- it was US policy to maintain that the status of Taiwan was undetermined, until that prize shit Henry Kissinger sold the island out during the Vietnam War negotiations in one of those archetypal FUBAR moves that are the invariable product of the real-men-decide-the-fate-of-nations crowd.
In fact in the whole history of the island no government has ever had undisputed control of both the entire island and the entirety of China. Chinese claims to Taiwan are simply expansionist fictions.
Gerrit van der Wees over on Taiwan Focus also pointed out that this too is in error:
Both colonial regimes clamped down very hard at first. Various estimates suggest the Japanese killed from 12,000 to 32,000 Taiwanese in their first few years of rule. The Chinese colonial regime killed 10,000 to 20,000 Taiwanese after the Feb. 28, 1947, uprising.
More reliable figures put out by the government in the early 1990s after the archives opened up are above 30,000. The numbers for deaths under the Japanese will never be known, but they are surely higher than 30,000. Pacification campaigns against the aborigines were conducted with great brutality, and entire villages were burned and regions stripped of their menfolk.
All in all, a great piece. Kudos to Jacob for a good thumbnail of the arguments, and for locating them in current scholarship.