I think a lot of Mao's deaths were actually unintentional. For example, he saw some birds eating crops and started a campaign to kill all the birds. People slaughtered them en masse and the insect pest problem exploded. Millions died from the famine.
Unintentionally killing people because of unforeseen consequences is a bit different from loading them in box cars and sending them to death camps.
Whether the murders committed by Communists under Chairman Mao were intentional or not does not matter to those who died. They died because of what an evil totalitarian regime did. But then fools who dither about nuance apparently think that because the murders were unintentional that the murderers are not responsible for them. Dead is dead, whether or not the deaths were intentional.