The key difference in premodern systems is that violence was usually a way to control or punish rebellion, not an expression of a racial ideology that marked a whole population as permanently inferior.
You keep asserting this, but it isn't true.
modern identity is tied to state categories that make identity rigid.
This also isn't actually true.
Really.

Modern identity is rigid because modern states institutionalize it through censuses, identity cards, legal classifications, and racialized administrative categories. This form of bureaucratically enforced identity did not exist in antiquity, where identities were socially inherited but still situational and permeable.
Here’s the problem with how you and NoHolyCows keep engaging me. You’re slicing my argument into isolated fragments instead of dealing with it as a whole. When I say fixed identities weren’t treated the same in antiquity, you both twist that into “he’s saying fixed identities didn’t exist at all.” You both remind me of bible thumpers who chop up passages so that context is irrelevant and the bible says whatever they want it to say.
My point is simple: in systems like caste, or in ancient empires, fixed identities still had
built-in pathways for incorporation, absorption, or assimilation. People had a place within the structure, even if it was hierarchical or oppressive. In modern ethnic cleansing, especially under a colonial identity framework, there is
no place for the targeted group. Their identity is treated as inescapable, and assimilation isn’t
built-in. That’s the context for Sudan, the people being targeted are marked as having
no place in the system, which is precisely what makes the violence ethnic cleansing rather than ancient-style conquest or stratification.
As for as modern identity not being rigid... OMG. I can't believe Emily of all people is making that claim.

The same Emily parading around this forum with tiki torch in hand over simple pronouns?