Not only Arabs but your statement with numbers is true. The old Egyptians moved, those who built the pyramids. Same as from Syria, 90% in Syria were not old Syrians who built the pyramids, but those who invaded-came in and old Syrians had to relocate under ruling pressure.
Similar is with Bosnia people, the original builders-descendants moved, but that is much older case, x4 older in time.
As example: One of the pyramids builders are Lebanon people-descendants , I can't tell you from which of those too, there would be conflict.