They used equality as a rhetorical pretext for empowering a different narrow elite that the one than the revolutionary cadre replaced.

Weird though that every time the same thing ended up happening.

USSR and Maoist PRC indeed took actions that killed millions, but so did capitalist India or mercantilist Britain or hegemonic America. I don't see a correlation between "forcing equality," which I'm not really even sure those regimes did (since Party members were clearly unequal in their power and quality of life), and the deaths. Just politics.