This is complicated so I'm not going to cover everything by any means, but I can discuss the qualities of symmetry if it's interesting?
Below is an image (same image reversed and overlaid on itself to express the qualities of perfection from side to side) of a fallen Rammeses statue head. Carved in granite, which is exceptionally difficult on this scale, and symmetrical in ways that are impossible to perfect on this scale without the use of a guided tool (this means a tool that has a preset path mechanism, completely outside the scope of "art"). This would have been exceptionally difficult to for us achieve 50 years ago, today it would be more mundane with the use of CAD programming and computer guided cutting tools.
NOTE: the face is of course not perfect, but it is exacting to levels only modern metrology can measure accurately and it is accurate to the same exceptional tolerances on both sides of the face. Things like the ear shapes are different, but again, the face from side to side is for all intents and purposes identical, again unachievable by the human eye or by accident...and let us not forget there are dozens and dozens of similar examples of this exact same symmetry in other Rammeses heads. It appears they had a rough machining process for getting the general shapes created, and hand artisans would go in and do the fine details.
For scale, and so you understand the monumental (literally task) of this. Here is a full statue (Dolomite or Granite, not sure which this is, pretty sure Granite).
It is one block of stone (outside the hedjet crown on top). It weighs something on the order of 450 tons, carved from an original block north of 600 tons.
The long and the short of the above is that they were undoubtedly using machine tools (powered by what I have no idea) and they were using guided track set tool systems that were "pre programmed"...though that doesn't mean they were computer aided by any means.
I'm happy to speculate till the cows come home about the above and there really is no other thing to do than to scratch ones head when presented with these ideas...but there it is.
Pyramids are a whole other kettle of wax but the above is a less discussed but equally impressive in many ways as an achievement. The tools necessary and used to create the Rammeses statues above simply do not exist in the archeological record.