I doubt this person has spent very long considering the suffering of the peasants and instead decided that Mao was an evil wizard who cast a spell on the peasantry. In reality, there were regions in China just prior to the land reform where peasants were made to pay genuinely 9/10 of their harvest and weren't treated very well even beyond this, as they were often enough conscripted into various sorts of unpaid labor like construction, politically completely voiceless due to landlords dominating local governance, beaten even just for perceived disrespect (to say nothing of crimes of want), publicly humiliated, subjected to SV in various forms, trapped in debt via malicious usury, and sold their own harvest back to them at inflated rates during times of famine.

I strongly believe in rehabilitative justice. If I grew up in their position, I would not hesitate to demand the deaths of the monsters who inflicted this on myself, my family, and my fellows, so I think the fact that so many landlords survived is, if anything, a testament to the mercy and pragmatism of the peasantry.