Like most things, it's not black and white. I don't think it is a stretch to say defending China from Japanese Conquest was good for China (and the WW2 allies)
They certainly weren't the "goodies". Chiang Kai Shek's regime was notoriously corrupt and authoritarian, but that they fought the Japanese invaders far more than Mao's communists did from their northern stronghold is indisputable. They often fought terribly, and in the Japanese Ichigo Offensive of 1944, Nationalist losses were catastrophic, but they also inflicted major material losses on the Japanese in turn. The communists did barely any of this in comparison. Mao was very self-serving in his tactics throughout the war and no less vicious/autocratic and corrupt regionally than Chiang.