It's a rather interesting fact that the Roman empire was generally simply sending out armies to extend its tax base, and thus destroying and genociding were not frequent events in their actions.

But they nearly completely exterminated the Cartaginians.

The DNA evidence shows that maybe one or two families survived.

What other unique thing is there about the the ancient city state of Carthage?

Oh yeah, https://www.theguardian.com/science/2014/jan/21/carthaginians-sacrificed-own-children-study

The Romans wanted these sickos to be wiped from the face of the earth, doubly so after they almost conquered Rome.