Class, education, profession are mostly about actions, actually. They just happen to be identities that are established by those actions. And (early) Soviets didn't consider any of that irredeemable either, as evidenced by many Imperial "white officers" later in employ of the Red Army.

So, no, it wasn't about any kind of a fundamental difference. That ideology didn't believe that there was any group of people to which common decency no longer applies. They believed that common decency no longer applies to anyone, because revolutionary necessity requires it. People who were deemed dangerous to that necessity were killed not because they were deemed subhuman, but solely because they were deemed to be a danger. They even reflected it in the criminal code - it didn't speak of "punishment", but rather of "means of social protection", and death penalty was euphemistically referred to as "the highest measure of social protection".