It was likely not the so-called ancient Egyptians (Egyptians of the Old Kingdom) that built the Gaza complex (it was built as one “interlocking” geometric structure), but by the Westerners whoever they were - their main areas of activity lie in the Nile Delta now under hundreds of feet of silt.
There is no way using modern machinery to build those structures - the internal stones are simply too heavy for any current crane to lift. They are not “stacked” stones, but fitted stones - each designed and ‘cut’ to have a specific sonic resonance tuned to the that type of stone’s crystalline structure; So that the entire structure has a specific resonance which can be herd in many videos of sounds made inside the structures. Why is unknown. But they were not tombs, but something else, for some other purpose which we likely would have a difficult time understanding - since the people of the Old Kingdom and later thought not linearly as we do, but symbolically.
PIF