I think it’s because Copts are Christian & therefore less likely to marry foreigners, mostly Arabs & such, which is why Copts are closer to ancient Egyptians than Muslim Egyptians are. Muslim Egyptians have more Arab DNA, making them less “Egyptian” compared to the average Copt.Let me see if I get this chart, basically distance means the group furthest away right?
Copts being closest to them would make sense since they use a language that descends from ancient egyptian language right?
The Muslim Egyptians abandoned their language & culture and adopted Arabic, the Coptic Egyptians retained their culture & language for the most part, making them the closest thing you’ll find to ancient Egyptians, don’t get me wrong the coptics probably also abandoned some parts of native Egyptian culture too in favour of Greek & Christian tradition. But they still retain a lot more of ancient Egyptian culture, including native Egyptian language, than the Muslims do.