A KR-like China would have been impossible for one major reason, Mao had at least a few things grounding him to reality; Pol Pot was just absolutely fucking bat guano. He invaded a country with several times the population (Vietnam) with the rationale that Vietnam's comparative modernisation and urbanisation would make it's people less tough.
Let's put this into perspective: Vietnam had just gotten past decades of protracted conflict against multiple foreign powers (Japan, France, the US, etc) based on the sheer motivation of its armed people. Pol Pot sincerely thought that his people were so much more tough and dedicated than that, that it would make up for a fivefold difference in population as well as greater levels of military and industrial development.
A lot of time Pol Pot's atrocities are simplified as 'he killed a ton of people', and while this is absolutely true, it leaves out the sheer degree to which his decisions were absolutely inane. I think that factor - an absurdly irrational totalitarian actor - is the hardest to replicate to get a KR situation out of any other country.
Agreed entirely. To make this clear, Pol Pot killed 25-33% of Cambodia in 4 years (1975-1979). Mao ruled China for 26 years. Whatever the death toll of Maoist policies were and to what degree you attribute them to Mao, no one says it comes even close to Pol Pot, even if Mao's massive time advantage. The same logic applies to Stalin and yes, even the Kims in North Korea.
In that sense, "Maoists win" ala Peru or Nepal is not a convincing KR scenario to me unless there's evidence that they were as totally crazy as Pol Pot was.