Rome was a multiethnic empire. I don't see what being Roman or not has to do with ethnicity.

The Roman people living there being ethically Berber, that is, African. The name Africa itself probably coming from the Afri Berber tribe. They were both Roman people and also ethnically African.

And Berber tribes despite not being from subsaharan Africa did, through thousands of years of contact, have significant ethnic and cultural admixture with various subsaharan African peoples. Not that North Africa is less African than subsaharan Africa.

You are completely and utterly wrong. That DNA was sampled by a Phoenician settler into North Africa of the Phoenician ruling class or Carthage. The vast minority of North Africans at that time had predominant Phoenician ancestry or lived in Phoenician culture.

North Africans are and always were the same people genetically. The North African emperors I am referring to specifically had Berber, not Punic or Phoenician ancestry. Which is still the dominant ancestry in North Africa today, and the Berber culture and language still lives on today.

Unfortunately it seems you are not knowledgeable of the history either of late Rome, of Carthage or of (North) Africa in general, and the authors of that website either did an incredibly poor job at it or are as well.