People did secondary analyses on those samples and found no real major ethnic turn over. You can detect admixture events even without having ancestral samples/ghost populations.No DNA tests were done pre- New Kingdom/Ptolemaic dynasty . So until this very day there is NO actual representative Ancient Egyptian sample.
Referring to Ptolemaic dynasty to New Kingdom as representative of the Ancient Egyptian sample is fraudulent. Even those who carried out the tests made a clear disclaimer saying that those tests are NOT representative.
So why do you keep pushing this narrative?
Don't hold your breath on Beja-like Ancient Egyptians. It won't happen. Ancient Nubia is where those people lived.
Ancient Egypt was based on Mesopotamian technology. They did not develop the basics of that civilization on their own. AE-Mesopotamian ties are super old.