That whole region has been flipped more times than a short stack at denny's
It is very difficult to ascertain if the people that live there now are descendants of the people who lived there over the millenia. In some cases yes, in others, no way.
The pyramids were incredibly ancient when Ramses II was Pharaoh and in the time of Akhenaten they were also ancient. By the time of the last Pharaoh (Cleopatra who wasn't even an egyptian) the old dynasties were almost forgotten.