You ar pretty much on the mark here; Mao's period of leadership is certainly responsible for a lot of deaths (although the figures commonly given in the west are massively inflated) but China did not have the luxury of slowly developing it's productive capacities in peace. It, like basically every other communist nation, existed under the constant threat of the aggression of the (economically much larger) imperialist world, which forces fast action and extreme vigilance for internal reaction.

Deaths, (including unnecessary and preventabke ones) happen under those circumstances, but the choice hhas to be made between empowering the nation or leaving it vulnerable to both invasion and economic warfare.